1	// Copyright (C) 2016 The Qt Company Ltd.
2	// Copyright (C) 2013 Samuel Gaist <samuel.gaist@deltech.ch>
3	// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
4
5	#include "qlistview.h"
6
7	#include <qabstractitemdelegate.h>
8	#if QT_CONFIG(accessibility)
9	#include <qaccessible.h>
10	#endif
11	#include <qapplication.h>
12	#include <qstylepainter.h>
13	#include <qbitmap.h>
14	#include <qdebug.h>
15	#if QT_CONFIG(draganddrop)
16	#include <qdrag.h>
17	#endif
18	#include <qevent.h>
19	#include <qlist.h>
20	#if QT_CONFIG(rubberband)
21	#include <qrubberband.h>
22	#endif
23	#include <qscrollbar.h>
24	#include <qstyle.h>
25	#include <private/qapplication_p.h>
26	#include <private/qlistview_p.h>
27	#include <private/qscrollbar_p.h>
28
29	#include <algorithm>
30
31	QT_BEGIN_NAMESPACE
32
33	extern bool qt_sendSpontaneousEvent(QObject *receiver, QEvent *event);
34
35	/*!
36	\class QListView
37
38	\brief The QListView class provides a list or icon view onto a model.
39
40	\ingroup model-view
41	\ingroup advanced
42	\inmodule QtWidgets
43
44	\image fusion-listview.png
45
46	A QListView presents items stored in a model, either as a simple
47	non-hierarchical list, or as a collection of icons. This class is used
48	to provide lists and icon views that were previously provided by the
49	\c QListBox and \c QIconView classes, but using the more flexible
50	approach provided by Qt's model/view architecture.
51
52	The QListView class is one of the \l{Model/View Classes}
53	and is part of Qt's \l{Model/View Programming}{model/view framework}.
54
55	This view does not display horizontal or vertical headers; to display
56	a list of items with a horizontal header, use QTreeView instead.
57
58	QListView implements the interfaces defined by the
59	QAbstractItemView class to allow it to display data provided by
60	models derived from the QAbstractItemModel class.
61
62	Items in a list view can be displayed using one of two view modes:
63	In \l ListMode, the items are displayed in the form of a simple list;
64	in \l IconMode, the list view takes the form of an \e{icon view} in
65	which the items are displayed with icons like files in a file manager.
66	By default, the list view is in \l ListMode. To change the view mode,
67	use the setViewMode() function, and to determine the current view mode,
68	use viewMode().
69
70	Items in these views are laid out in the direction specified by the
71	flow() of the list view. The items may be fixed in place, or allowed
72	to move, depending on the view's movement() state.
73
74	If the items in the model cannot be completely laid out in the
75	direction of flow, they can be wrapped at the boundary of the view
76	widget; this depends on isWrapping(). This property is useful when the
77	items are being represented by an icon view.
78
79	The resizeMode() and layoutMode() govern how and when the items are
80	laid out. Items are spaced according to their spacing(), and can exist
81	within a notional grid of size specified by gridSize(). The items can
82	be rendered as large or small icons depending on their iconSize().
83
84	\section1 Improving Performance
85
86	It is possible to give the view hints about the data it is handling in order
87	to improve its performance when displaying large numbers of items. One approach
88	that can be taken for views that are intended to display items with equal sizes
89	is to set the \l uniformItemSizes property to true.
90
91	\sa {View Classes}, QTreeView, QTableView, QListWidget
92	*/
93
94	/*!
95	\enum QListView::ViewMode
96
97	\value ListMode The items are laid out using TopToBottom flow, with Small size and Static movement
98	\value IconMode The items are laid out using LeftToRight flow, with Large size and Free movement
99	*/
100
101	/*!
102	\enum QListView::Movement
103
104	\value Static The items cannot be moved by the user.
105	\value Free The items can be moved freely by the user.
106	\value Snap The items snap to the specified grid when moved; see
107	setGridSize().
108	*/
109
110	/*!
111	\enum QListView::Flow
112
113	\value LeftToRight The items are laid out in the view from the left
114	to the right.
115	\value TopToBottom The items are laid out in the view from the top
116	to the bottom.
117	*/
118
119	/*!
120	\enum QListView::ResizeMode
121
122	\value Fixed The items will only be laid out the first time the view is shown.
123	\value Adjust The items will be laid out every time the view is resized.
124	*/
125
126	/*!
127	\enum QListView::LayoutMode
128
129	\value SinglePass The items are laid out all at once.
130	\value Batched The items are laid out in batches of \l batchSize items.
131	\sa batchSize
132	*/
133
134	/*!
135	\since 4.2
136	\fn void QListView::indexesMoved(const QModelIndexList &indexes)
137
138	This signal is emitted when the specified \a indexes are moved in the view.
139	*/
140
141	/*!
142	Creates a new QListView with the given \a parent to view a model.
143	Use setModel() to set the model.
144	*/
145	QListView::QListView(QWidget *parent)
146	: QAbstractItemView(*new QListViewPrivate, parent)
147	{
148	setViewMode(ListMode);
149	setSelectionMode(SingleSelection);
150	setAttribute(Qt::WA_MacShowFocusRect);
151	Q_D(QListView); // We rely on a qobject_cast for PM_DefaultFrameWidth to change
152	d->updateStyledFrameWidths(); // hence we have to force an update now that the object has been constructed
153	}
154
155	/*!
156	\internal
157	*/
158	QListView::QListView(QListViewPrivate &dd, QWidget *parent)
159	: QAbstractItemView(dd, parent)
160	{
161	setViewMode(ListMode);
162	setSelectionMode(SingleSelection);
163	setAttribute(Qt::WA_MacShowFocusRect);
164	Q_D(QListView); // We rely on a qobject_cast for PM_DefaultFrameWidth to change
165	d->updateStyledFrameWidths(); // hence we have to force an update now that the object has been constructed
166	}
167
168	/*!
169	Destroys the view.
170	*/
171	QListView::~QListView()
172	{
173	}
174
175	/*!
176	\property QListView::movement
177	\brief whether the items can be moved freely, are snapped to a
178	grid, or cannot be moved at all.
179
180	This property determines how the user can move the items in the
181	view. \l Static means that the items can't be moved by the user.
182	\l Free means that the user can drag and drop the items to any
183	position in the view. \l Snap means that the user can drag and
184	drop the items, but only to the positions in a notional grid
185	signified by the gridSize property.
186
187	Setting this property when the view is visible will cause the
188	items to be laid out again.
189
190	By default, this property is set to \l Static.
191
192	\sa gridSize, resizeMode, viewMode
193	*/
194	void QListView::setMovement(Movement movement)
195	{
196	Q_D(QListView);
197	d->modeProperties |= uint(QListViewPrivate::Movement);
198	d->movement = movement;
199
200	#if QT_CONFIG(draganddrop)
201	bool movable = (movement != Static);
202	setDragEnabled(movable);
203	d->viewport->setAcceptDrops(movable);
204	#endif
205	d->doDelayedItemsLayout();
206	}
207
208	QListView::Movement QListView::movement() const
209	{
210	Q_D(const QListView);
211	return d->movement;
212	}
213
214	/*!
215	\property QListView::flow
216	\brief which direction the items layout should flow.
217
218	If this property is \l LeftToRight, the items will be laid out left
219	to right. If the \l isWrapping property is \c true, the layout will wrap
220	when it reaches the right side of the visible area. If this
221	property is \l TopToBottom, the items will be laid out from the top
222	of the visible area, wrapping when it reaches the bottom.
223
224	Setting this property when the view is visible will cause the
225	items to be laid out again.
226
227	By default, this property is set to \l TopToBottom.
228
229	\sa viewMode
230	*/
231	void QListView::setFlow(Flow flow)
232	{
233	Q_D(QListView);
234	d->modeProperties |= uint(QListViewPrivate::Flow);
235	d->flow = flow;
236	d->doDelayedItemsLayout();
237	}
238
239	QListView::Flow QListView::flow() const
240	{
241	Q_D(const QListView);
242	return d->flow;
243	}
244
245	/*!
246	\property QListView::isWrapping
247	\brief whether the items layout should wrap.
248
249	This property holds whether the layout should wrap when there is
250	no more space in the visible area. The point at which the layout wraps
251	depends on the \l flow property.
252
253	Setting this property when the view is visible will cause the
254	items to be laid out again.
255
256	By default, this property is \c false.
257
258	\sa viewMode
259	*/
260	void QListView::setWrapping(bool enable)
261	{
262	Q_D(QListView);
263	d->modeProperties |= uint(QListViewPrivate::Wrap);
264	d->setWrapping(enable);
265	d->doDelayedItemsLayout();
266	}
267
268	bool QListView::isWrapping() const
269	{
270	Q_D(const QListView);
271	return d->isWrapping();
272	}
273
274	/*!
275	\property QListView::resizeMode
276	\brief whether the items are laid out again when the view is resized.
277
278	If this property is \l Adjust, the items will be laid out again
279	when the view is resized. If the value is \l Fixed, the items will
280	not be laid out when the view is resized.
281
282	By default, this property is set to \l Fixed.
283
284	\sa movement, gridSize, viewMode
285	*/
286	void QListView::setResizeMode(ResizeMode mode)
287	{
288	Q_D(QListView);
289	d->modeProperties |= uint(QListViewPrivate::ResizeMode);
290	d->resizeMode = mode;
291	}
292
293	QListView::ResizeMode QListView::resizeMode() const
294	{
295	Q_D(const QListView);
296	return d->resizeMode;
297	}
298
299	/*!
300	\property QListView::layoutMode
301	\brief determines whether the layout of items should happen immediately or be delayed.
302
303	This property holds the layout mode for the items. When the mode
304	is \l SinglePass (the default), the items are laid out all in one go.
305	When the mode is \l Batched, the items are laid out in batches of \l batchSize
306	items, while processing events. This makes it possible to
307	instantly view and interact with the visible items while the rest
308	are being laid out.
309
310	\sa viewMode
311	*/
312	void QListView::setLayoutMode(LayoutMode mode)
313	{
314	Q_D(QListView);
315	d->layoutMode = mode;
316	}
317
318	QListView::LayoutMode QListView::layoutMode() const
319	{
320	Q_D(const QListView);
321	return d->layoutMode;
322	}
323
324	/*!
325	\property QListView::spacing
326	\brief the space around the items in the layout
327
328	This property is the size of the empty space that is padded around
329	an item in the layout.
330
331	Setting this property when the view is visible will cause the
332	items to be laid out again.
333
334	By default, this property contains a value of 0.
335
336	\sa viewMode
337	*/
338	void QListView::setSpacing(int space)
339	{
340	Q_D(QListView);
341	d->modeProperties |= uint(QListViewPrivate::Spacing);
342	d->setSpacing(space);
343	d->doDelayedItemsLayout();
344	}
345
346	int QListView::spacing() const
347	{
348	Q_D(const QListView);
349	return d->spacing();
350	}
351
352	/*!
353	\property QListView::batchSize
354	\brief the number of items laid out in each batch if \l layoutMode is
355	set to \l Batched.
356
357	The default value is 100.
358
359	\since 4.2
360	*/
361
362	void QListView::setBatchSize(int batchSize)
363	{
364	Q_D(QListView);
365	if (Q_UNLIKELY(batchSize <= 0)) {
366	qWarning(msg: "Invalid batchSize (%d)", batchSize);
367	return;
368	}
369	d->batchSize = batchSize;
370	}
371
372	int QListView::batchSize() const
373	{
374	Q_D(const QListView);
375	return d->batchSize;
376	}
377
378	/*!
379	\property QListView::gridSize
380	\brief the size of the layout grid
381
382	This property is the size of the grid in which the items are laid
383	out. The default is an empty size which means that there is no
384	grid and the layout is not done in a grid. Setting this property
385	to a non-empty size switches on the grid layout. (When a grid
386	layout is in force the \l spacing property is ignored.)
387
388	Setting this property when the view is visible will cause the
389	items to be laid out again.
390
391	\sa viewMode
392	*/
393	void QListView::setGridSize(const QSize &size)
394	{
395	Q_D(QListView);
396	d->modeProperties |= uint(QListViewPrivate::GridSize);
397	d->setGridSize(size);
398	d->doDelayedItemsLayout();
399	}
400
401	QSize QListView::gridSize() const
402	{
403	Q_D(const QListView);
404	return d->gridSize();
405	}
406
407	/*!
408	\property QListView::viewMode
409	\brief the view mode of the QListView.
410
411	This property will change the other unset properties to conform
412	with the set view mode. QListView-specific properties that have already been set
413	will not be changed, unless clearPropertyFlags() has been called.
414
415	Setting the view mode will enable or disable drag and drop based on the
416	selected movement. For ListMode, the default movement is \l Static
417	(drag and drop disabled); for IconMode, the default movement is
418	\l Free (drag and drop enabled).
419
420	\sa isWrapping, spacing, gridSize, flow, movement, resizeMode
421	*/
422	void QListView::setViewMode(ViewMode mode)
423	{
424	Q_D(QListView);
425	if (d->commonListView && d->viewMode == mode)
426	return;
427	d->viewMode = mode;
428
429	delete d->commonListView;
430	if (mode == ListMode) {
431	d->commonListView = new QListModeViewBase(this, d);
432	if (!(d->modeProperties & QListViewPrivate::Wrap))
433	d->setWrapping(false);
434	if (!(d->modeProperties & QListViewPrivate::Spacing))
435	d->setSpacing(0);
436	if (!(d->modeProperties & QListViewPrivate::GridSize))
437	d->setGridSize(QSize());
438	if (!(d->modeProperties & QListViewPrivate::Flow))
439	d->flow = TopToBottom;
440	if (!(d->modeProperties & QListViewPrivate::Movement))
441	d->movement = Static;
442	if (!(d->modeProperties & QListViewPrivate::ResizeMode))
443	d->resizeMode = Fixed;
444	if (!(d->modeProperties & QListViewPrivate::SelectionRectVisible))
445	d->showElasticBand = false;
446	} else {
447	d->commonListView = new QIconModeViewBase(this, d);
448	if (!(d->modeProperties & QListViewPrivate::Wrap))
449	d->setWrapping(true);
450	if (!(d->modeProperties & QListViewPrivate::Spacing))
451	d->setSpacing(0);
452	if (!(d->modeProperties & QListViewPrivate::GridSize))
453	d->setGridSize(QSize());
454	if (!(d->modeProperties & QListViewPrivate::Flow))
455	d->flow = LeftToRight;
456	if (!(d->modeProperties & QListViewPrivate::Movement))
457	d->movement = Free;
458	if (!(d->modeProperties & QListViewPrivate::ResizeMode))
459	d->resizeMode = Fixed;
460	if (!(d->modeProperties & QListViewPrivate::SelectionRectVisible))
461	d->showElasticBand = true;
462	}
463
464	#if QT_CONFIG(draganddrop)
465	bool movable = (d->movement != Static);
466	setDragEnabled(movable);
467	setAcceptDrops(movable);
468	#endif
469	d->clear();
470	d->doDelayedItemsLayout();
471	}
472
473	QListView::ViewMode QListView::viewMode() const
474	{
475	Q_D(const QListView);
476	return d->viewMode;
477	}
478
479	/*!
480	Clears the QListView-specific property flags. See \l{viewMode}.
481
482	Properties inherited from QAbstractItemView are not covered by the
483	property flags. Specifically, \l{QAbstractItemView::dragEnabled}
484	{dragEnabled} and \l{QAbstractItemView::acceptDrops}
485	{acceptsDrops} are computed by QListView when calling
486	setMovement() or setViewMode().
487	*/
488	void QListView::clearPropertyFlags()
489	{
490	Q_D(QListView);
491	d->modeProperties = 0;
492	}
493
494	/*!
495	Returns \c true if the \a row is hidden; otherwise returns \c false.
496	*/
497	bool QListView::isRowHidden(int row) const
498	{
499	Q_D(const QListView);
500	return d->isHidden(row);
501	}
502
503	/*!
504	If \a hide is true, the given \a row will be hidden; otherwise
505	the \a row will be shown.
506	*/
507	void QListView::setRowHidden(int row, bool hide)
508	{
509	Q_D(QListView);
510	const bool hidden = d->isHidden(row);
511	if (hide && !hidden)
512	d->commonListView->appendHiddenRow(row);
513	else if (!hide && hidden)
514	d->commonListView->removeHiddenRow(row);
515	d->doDelayedItemsLayout();
516	d->viewport->update();
517	}
518
519	/*!
520	\reimp
521	*/
522	QRect QListView::visualRect(const QModelIndex &index) const
523	{
524	Q_D(const QListView);
525	return d->mapToViewport(rect: rectForIndex(index));
526	}
527
528	/*!
529	\reimp
530	*/
531	void QListView::scrollTo(const QModelIndex &index, ScrollHint hint)
532	{
533	Q_D(QListView);
534
535	if (index.parent() != d->root || index.column() != d->column)
536	return;
537
538	const QRect rect = visualRect(index);
539	if (!rect.isValid())
540	return;
541	if (hint == EnsureVisible && d->viewport->rect().contains(r: rect)) {
542	d->viewport->update(rect);
543	return;
544	}
545
546	if (d->flow == QListView::TopToBottom || d->isWrapping()) // vertical
547	verticalScrollBar()->setValue(d->verticalScrollToValue(index, rect, hint));
548
549	if (d->flow == QListView::LeftToRight || d->isWrapping()) // horizontal
550	horizontalScrollBar()->setValue(d->horizontalScrollToValue(index, rect, hint));
551	}
552
553	int QListViewPrivate::horizontalScrollToValue(const QModelIndex &index, const QRect &rect,
554	QListView::ScrollHint hint) const
555	{
556	Q_Q(const QListView);
557	const QRect area = viewport->rect();
558	const bool leftOf = q->isRightToLeft()
559	? (rect.left() < area.left()) && (rect.right() < area.right())
560	: rect.left() < area.left();
561	const bool rightOf = q->isRightToLeft()
562	? rect.right() > area.right()
563	: (rect.right() > area.right()) && (rect.left() > area.left());
564	return commonListView->horizontalScrollToValue(index: q->visualIndex(index), hint, leftOf, rightOf, area, rect);
565	}
566
567	int QListViewPrivate::verticalScrollToValue(const QModelIndex &index, const QRect &rect,
568	QListView::ScrollHint hint) const
569	{
570	Q_Q(const QListView);
571	const QRect area = viewport->rect();
572	const bool above = (hint == QListView::EnsureVisible && rect.top() < area.top());
573	const bool below = (hint == QListView::EnsureVisible && rect.bottom() > area.bottom());
574	return commonListView->verticalScrollToValue(index: q->visualIndex(index), hint, above, below, area, rect);
575	}
576
577	void QListViewPrivate::selectAll(QItemSelectionModel::SelectionFlags command)
578	{
579	if (!selectionModel)
580	return;
581
582	QItemSelection selection;
583	QModelIndex topLeft;
584	int row = 0;
585	const int colCount = model->columnCount(parent: root);
586	const int rowCount = model->rowCount(parent: root);
587	for ( ; row < rowCount; ++row) {
588	if (isHidden(row)) {
589	//it might be the end of a selection range
590	if (topLeft.isValid()) {
591	QModelIndex bottomRight = model->index(row: row - 1, column: colCount - 1, parent: root);
592	selection.append(t: QItemSelectionRange(topLeft, bottomRight));
593	topLeft = QModelIndex();
594	}
595	continue;
596	}
597
598	if (!topLeft.isValid()) //start of a new selection range
599	topLeft = model->index(row, column: 0, parent: root);
600	}
601
602	if (topLeft.isValid()) {
603	//last selected range
604	QModelIndex bottomRight = model->index(row: row - 1, column: colCount - 1, parent: root);
605	selection.append(t: QItemSelectionRange(topLeft, bottomRight));
606	}
607
608	if (!selection.isEmpty())
609	selectionModel->select(selection, command);
610	}
611
612	/*!
613	\reimp
614
615	We have a QListView way of knowing what elements are on the viewport
616	through the intersectingSet function
617	*/
618	QItemViewPaintPairs QListViewPrivate::draggablePaintPairs(const QModelIndexList &indexes, QRect *r) const
619	{
620	Q_ASSERT(r);
621	Q_Q(const QListView);
622	QRect &rect = *r;
623	const QRect viewportRect = viewport->rect();
624	QItemViewPaintPairs ret;
625	QList<QModelIndex> visibleIndexes =
626	intersectingSet(area: viewportRect.translated(dx: q->horizontalOffset(), dy: q->verticalOffset()));
627	std::sort(first: visibleIndexes.begin(), last: visibleIndexes.end());
628	for (const auto &index : indexes) {
629	if (std::binary_search(first: visibleIndexes.cbegin(), last: visibleIndexes.cend(), val: index)) {
630	const QRect current = q->visualRect(index);
631	ret.append(t: {.rect: current, .index: index});
632	rect |= current;
633	}
634	}
635	QRect clipped = rect & viewportRect;
636	rect.setLeft(clipped.left());
637	rect.setRight(clipped.right());
638	return ret;
639	}
640
641	/*!
642	\internal
643	*/
644	void QListView::reset()
645	{
646	Q_D(QListView);
647	d->clear();
648	d->hiddenRows.clear();
649	QAbstractItemView::reset();
650	}
651
652	/*!
653	\reimp
654	*/
655	void QListView::setRootIndex(const QModelIndex &index)
656	{
657	Q_D(QListView);
658	d->column = qMax(a: 0, b: qMin(a: d->column, b: d->model->columnCount(parent: index) - 1));
659	QAbstractItemView::setRootIndex(index);
660	// sometimes we get an update before reset() is called
661	d->clear();
662	d->hiddenRows.clear();
663	}
664
665	/*!
666	\reimp
667
668	Scroll the view contents by \a dx and \a dy.
669	*/
670
671	void QListView::scrollContentsBy(int dx, int dy)
672	{
673	Q_D(QListView);
674	d->delayedAutoScroll.stop(); // auto scroll was canceled by the user scrolling
675	d->commonListView->scrollContentsBy(dx, dy, scrollElasticBand: d->state == QListView::DragSelectingState);
676	}
677
678	/*!
679	\internal
680
681	Resize the internal contents to \a width and \a height and set the
682	scroll bar ranges accordingly.
683	*/
684	void QListView::resizeContents(int width, int height)
685	{
686	Q_D(QListView);
687	d->setContentsSize(w: width, h: height);
688	}
689
690	/*!
691	\internal
692	*/
693	QSize QListView::contentsSize() const
694	{
695	Q_D(const QListView);
696	return d->contentsSize();
697	}
698
699	/*!
700	\reimp
701	*/
702	void QListView::dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight,
703	const QList<int> &roles)
704	{
705	d_func()->commonListView->dataChanged(topLeft, bottomRight);
706	QAbstractItemView::dataChanged(topLeft, bottomRight, roles);
707	}
708
709	/*!
710	\reimp
711	*/
712	void QListView::rowsInserted(const QModelIndex &parent, int start, int end)
713	{
714	Q_D(QListView);
715	// ### be smarter about inserted items
716	d->clear();
717	d->doDelayedItemsLayout();
718	QAbstractItemView::rowsInserted(parent, start, end);
719	}
720
721	/*!
722	\reimp
723	*/
724	void QListView::rowsAboutToBeRemoved(const QModelIndex &parent, int start, int end)
725	{
726	Q_D(QListView);
727	// if the parent is above d->root in the tree, nothing will happen
728	QAbstractItemView::rowsAboutToBeRemoved(parent, start, end);
729	if (parent == d->root) {
730	QSet<QPersistentModelIndex>::iterator it = d->hiddenRows.begin();
731	while (it != d->hiddenRows.end()) {
732	int hiddenRow = it->row();
733	if (hiddenRow >= start && hiddenRow <= end) {
734	it = d->hiddenRows.erase(i: it);
735	} else {
736	++it;
737	}
738	}
739	}
740	d->clear();
741	d->doDelayedItemsLayout();
742	}
743
744	/*!
745	\reimp
746	*/
747	void QListView::mouseMoveEvent(QMouseEvent *e)
748	{
749	if (!isVisible())
750	return;
751	Q_D(QListView);
752	QAbstractItemView::mouseMoveEvent(event: e);
753	if (state() == DragSelectingState
754	&& d->showElasticBand
755	&& d->selectionMode != SingleSelection
756	&& d->selectionMode != NoSelection) {
757	QRect rect(d->pressedPosition, e->position().toPoint() + QPoint(horizontalOffset(), verticalOffset()));
758	rect = rect.normalized();
759	const int margin = 2 * style()->pixelMetric(metric: QStyle::PM_DefaultFrameWidth);
760	const QRect viewPortRect = rect.united(r: d->elasticBand)
761	.adjusted(xp1: -margin, yp1: -margin, xp2: margin, yp2: margin);
762	d->viewport->update(d->mapToViewport(rect: viewPortRect));
763	d->elasticBand = rect;
764	}
765	}
766
767	/*!
768	\reimp
769	*/
770	void QListView::mouseReleaseEvent(QMouseEvent *e)
771	{
772	Q_D(QListView);
773	QAbstractItemView::mouseReleaseEvent(event: e);
774	// #### move this implementation into a dynamic class
775	if (d->showElasticBand && d->elasticBand.isValid()) {
776	const int margin = 2 * style()->pixelMetric(metric: QStyle::PM_DefaultFrameWidth);
777	const QRect viewPortRect = d->elasticBand.adjusted(xp1: -margin, yp1: -margin, xp2: margin, yp2: margin);
778	d->viewport->update(d->mapToViewport(rect: viewPortRect));
779	d->elasticBand = QRect();
780	}
781	}
782
783	#if QT_CONFIG(wheelevent)
784	/*!
785	\reimp
786	*/
787	void QListView::wheelEvent(QWheelEvent *e)
788	{
789	Q_D(QListView);
790	if (qAbs(t: e->angleDelta().y()) > qAbs(t: e->angleDelta().x())) {
791	if (e->angleDelta().x() == 0
792	&& ((d->flow == TopToBottom && d->wrap) || (d->flow == LeftToRight && !d->wrap))
793	&& d->vbar->minimum() == 0 && d->vbar->maximum() == 0) {
794	QPoint pixelDelta(e->pixelDelta().y(), e->pixelDelta().x());
795	QPoint angleDelta(e->angleDelta().y(), e->angleDelta().x());
796	QWheelEvent hwe(e->position(), e->globalPosition(), pixelDelta, angleDelta,
797	e->buttons(), e->modifiers(), e->phase(), e->inverted(), e->source());
798	if (e->spontaneous())
799	qt_sendSpontaneousEvent(receiver: d->hbar, event: &hwe);
800	else
801	QCoreApplication::sendEvent(receiver: d->hbar, event: &hwe);
802	e->setAccepted(hwe.isAccepted());
803	} else {
804	QCoreApplication::sendEvent(receiver: d->vbar, event: e);
805	}
806	} else {
807	QCoreApplication::sendEvent(receiver: d->hbar, event: e);
808	}
809	}
810	#endif // QT_CONFIG(wheelevent)
811
812	/*!
813	\reimp
814	*/
815	void QListView::timerEvent(QTimerEvent *e)
816	{
817	Q_D(QListView);
818	if (e->timerId() == d->batchLayoutTimer.timerId()) {
819	if (d->doItemsLayout(num: d->batchSize)) { // layout is done
820	d->batchLayoutTimer.stop();
821	updateGeometries();
822	d->viewport->update();
823	}
824	}
825	QAbstractItemView::timerEvent(event: e);
826	}
827
828	/*!
829	\reimp
830	*/
831	void QListView::resizeEvent(QResizeEvent *e)
832	{
833	Q_D(QListView);
834	if (d->delayedPendingLayout)
835	return;
836
837	QSize delta = e->size() - e->oldSize();
838
839	if (delta.isNull())
840	return;
841
842	bool listWrap = (d->viewMode == ListMode) && d->wrapItemText;
843	bool flowDimensionChanged = (d->flow == LeftToRight && delta.width() != 0)
844	|| (d->flow == TopToBottom && delta.height() != 0);
845
846	// We post a delayed relayout in the following cases :
847	// - we're wrapping
848	// - the state is NoState, we're adjusting and the size has changed in the flowing direction
849	if (listWrap
850	|| (state() == NoState && d->resizeMode == Adjust && flowDimensionChanged)) {
851	d->doDelayedItemsLayout(delay: 100); // wait 1/10 sec before starting the layout
852	} else {
853	QAbstractItemView::resizeEvent(event: e);
854	}
855	}
856
857	#if QT_CONFIG(draganddrop)
858
859	/*!
860	\reimp
861	*/
862	void QListView::dragMoveEvent(QDragMoveEvent *e)
863	{
864	Q_D(QListView);
865	if (!d->commonListView->filterDragMoveEvent(e)) {
866	if (viewMode() == QListView::ListMode && flow() == QListView::LeftToRight)
867	static_cast<QListModeViewBase *>(d->commonListView)->dragMoveEvent(e);
868	else
869	QAbstractItemView::dragMoveEvent(event: e);
870	}
871	}
872
873
874	/*!
875	\reimp
876	*/
877	void QListView::dragLeaveEvent(QDragLeaveEvent *e)
878	{
879	if (!d_func()->commonListView->filterDragLeaveEvent(e))
880	QAbstractItemView::dragLeaveEvent(event: e);
881	}
882
883	/*!
884	\reimp
885	*/
886	void QListView::dropEvent(QDropEvent *event)
887	{
888	Q_D(QListView);
889
890	const bool moveAction = event->dropAction() == Qt::MoveAction
891	|| dragDropMode() == QAbstractItemView::InternalMove;
892	if (event->source() == this && moveAction) {
893	QModelIndex topIndex;
894	bool topIndexDropped = false;
895	int col = -1;
896	int row = -1;
897	// check whether a subclass has already accepted the event, ie. moved the data
898	if (!event->isAccepted() && d->dropOn(event, row: &row, col: &col, index: &topIndex)) {
899	const QList<QModelIndex> selIndexes = selectedIndexes();
900	QList<QPersistentModelIndex> persIndexes;
901	persIndexes.reserve(asize: selIndexes.size());
902
903	for (const auto &index : selIndexes) {
904	persIndexes.append(t: index);
905	if (index == topIndex) {
906	topIndexDropped = true;
907	break;
908	}
909	}
910
911	if (!topIndexDropped && !topIndex.isValid()) {
912	std::sort(first: persIndexes.begin(), last: persIndexes.end()); // The dropped items will remain in the same visual order.
913
914	QPersistentModelIndex dropRow = model()->index(row, column: col, parent: topIndex);
915
916	int r = row == -1 ? model()->rowCount() : (dropRow.row() >= 0 ? dropRow.row() : row);
917	bool dataMoved = false;
918	for (int i = 0; i < persIndexes.size(); ++i) {
919	const QPersistentModelIndex &pIndex = persIndexes.at(i);
920	// only generate a move when not same row or behind itself
921	if (r != pIndex.row() && r != pIndex.row() + 1) {
922	// try to move (preserves selection)
923	const bool moved = model()->moveRow(sourceParent: QModelIndex(), sourceRow: pIndex.row(), destinationParent: QModelIndex(), destinationChild: r);
924	if (!moved)
925	continue; // maybe it'll work for other rows
926	dataMoved = true; // success
927	} else {
928	// move onto itself is blocked, don't delete anything
929	dataMoved = true;
930	}
931	r = pIndex.row() + 1; // Dropped items are inserted contiguously and in the right order.
932	}
933	if (dataMoved)
934	event->accept();
935	}
936	}
937
938	// either we or a subclass accepted the move event, so assume that the data was
939	// moved and that QAbstractItemView shouldn't remove the source when QDrag::exec returns
940	if (event->isAccepted())
941	d->dropEventMoved = true;
942	}
943
944	if (!d->commonListView->filterDropEvent(event) || !d->dropEventMoved) {
945	// icon view didn't move the data, and moveRows not implemented, so fall back to default
946	if (!d->dropEventMoved && moveAction)
947	event->ignore();
948	QAbstractItemView::dropEvent(event);
949	}
950	}
951
952	/*!
953	\reimp
954	*/
955	void QListView::startDrag(Qt::DropActions supportedActions)
956	{
957	if (!d_func()->commonListView->filterStartDrag(supportedActions))
958	QAbstractItemView::startDrag(supportedActions);
959	}
960
961	#endif // QT_CONFIG(draganddrop)
962
963	/*!
964	\reimp
965	*/
966	void QListView::initViewItemOption(QStyleOptionViewItem *option) const
967	{
968	Q_D(const QListView);
969	QAbstractItemView::initViewItemOption(option);
970	if (!d->iconSize.isValid()) { // otherwise it was already set in abstractitemview
971	int pm = (d->viewMode == QListView::ListMode
972	? style()->pixelMetric(metric: QStyle::PM_ListViewIconSize, option: nullptr, widget: this)
973	: style()->pixelMetric(metric: QStyle::PM_IconViewIconSize, option: nullptr, widget: this));
974	option->decorationSize = QSize(pm, pm);
975	}
976	if (d->viewMode == QListView::IconMode) {
977	option->showDecorationSelected = false;
978	option->decorationPosition = QStyleOptionViewItem::Top;
979	option->displayAlignment = Qt::AlignCenter;
980	} else {
981	option->decorationPosition = QStyleOptionViewItem::Left;
982	}
983
984	if (d->gridSize().isValid()) {
985	option->rect.setSize(d->gridSize());
986	}
987	}
988
989
990	/*!
991	\reimp
992	*/
993	void QListView::paintEvent(QPaintEvent *e)
994	{
995	Q_D(QListView);
996	if (!d->itemDelegate)
997	return;
998	QStyleOptionViewItem option;
999	initViewItemOption(option: &option);
1000	QStylePainter painter(d->viewport);
1001
1002	const QList<QModelIndex> toBeRendered =
1003	d->intersectingSet(area: e->rect().translated(dx: horizontalOffset(), dy: verticalOffset()), doLayout: false);
1004
1005	const QModelIndex current = currentIndex();
1006	const QModelIndex hover = d->hover;
1007	const QAbstractItemModel *itemModel = d->model;
1008	const QItemSelectionModel *selections = d->selectionModel;
1009	const bool focus = (hasFocus() || d->viewport->hasFocus()) && current.isValid();
1010	const bool alternate = d->alternatingColors;
1011	const QStyle::State state = option.state;
1012	const QAbstractItemView::State viewState = this->state();
1013	const bool enabled = (state & QStyle::State_Enabled) != 0;
1014
1015	bool alternateBase = false;
1016	int previousRow = -2; // trigger the alternateBase adjustment on first pass
1017
1018	int maxSize = (flow() == TopToBottom)
1019	? qMax(a: viewport()->size().width(), b: d->contentsSize().width()) - 2 * d->spacing()
1020	: qMax(a: viewport()->size().height(), b: d->contentsSize().height()) - 2 * d->spacing();
1021
1022	QList<QModelIndex>::const_iterator end = toBeRendered.constEnd();
1023	for (QList<QModelIndex>::const_iterator it = toBeRendered.constBegin(); it != end; ++it) {
1024	Q_ASSERT((*it).isValid());
1025	option.rect = visualRect(index: *it);
1026
1027	if (flow() == TopToBottom)
1028	option.rect.setWidth(qMin(a: maxSize, b: option.rect.width()));
1029	else
1030	option.rect.setHeight(qMin(a: maxSize, b: option.rect.height()));
1031
1032	option.state = state;
1033	if (selections && selections->isSelected(index: *it))
1034	option.state |= QStyle::State_Selected;
1035	if (enabled) {
1036	QPalette::ColorGroup cg;
1037	if ((itemModel->flags(index: *it) & Qt::ItemIsEnabled) == 0) {
1038	option.state &= ~QStyle::State_Enabled;
1039	cg = QPalette::Disabled;
1040	} else {
1041	cg = QPalette::Normal;
1042	}
1043	option.palette.setCurrentColorGroup(cg);
1044	}
1045	if (focus && current == *it) {
1046	option.state |= QStyle::State_HasFocus;
1047	if (viewState == EditingState)
1048	option.state |= QStyle::State_Editing;
1049	}
1050	option.state.setFlag(flag: QStyle::State_MouseOver, on: *it == hover);
1051
1052	if (alternate) {
1053	int row = (*it).row();
1054	if (row != previousRow + 1) {
1055	// adjust alternateBase according to rows in the "gap"
1056	if (!d->hiddenRows.isEmpty()) {
1057	for (int r = qMax(a: previousRow + 1, b: 0); r < row; ++r) {
1058	if (!d->isHidden(row: r))
1059	alternateBase = !alternateBase;
1060	}
1061	} else {
1062	alternateBase = (row & 1) != 0;
1063	}
1064	}
1065	option.features.setFlag(flag: QStyleOptionViewItem::Alternate, on: alternateBase);
1066
1067	// draw background of the item (only alternate row). rest of the background
1068	// is provided by the delegate
1069	QStyle::State oldState = option.state;
1070	option.state &= ~QStyle::State_Selected;
1071	painter.drawPrimitive(pe: QStyle::PE_PanelItemViewRow, opt: option);
1072	option.state = oldState;
1073
1074	alternateBase = !alternateBase;
1075	previousRow = row;
1076	}
1077
1078	itemDelegateForIndex(index: *it)->paint(painter: &painter, option, index: *it);
1079	}
1080
1081	#if QT_CONFIG(draganddrop)
1082	d->commonListView->paintDragDrop(painter: &painter);
1083	#endif
1084
1085	#if QT_CONFIG(rubberband)
1086	// #### move this implementation into a dynamic class
1087	if (d->showElasticBand && d->elasticBand.isValid()) {
1088	QStyleOptionRubberBand opt;
1089	opt.initFrom(w: this);
1090	opt.shape = QRubberBand::Rectangle;
1091	opt.opaque = false;
1092	opt.rect = d->mapToViewport(rect: d->elasticBand, extend: false).intersected(
1093	other: d->viewport->rect().adjusted(xp1: -16, yp1: -16, xp2: 16, yp2: 16));
1094	painter.save();
1095	painter.drawControl(ce: QStyle::CE_RubberBand, opt);
1096	painter.restore();
1097	}
1098	#endif
1099	}
1100
1101	/*!
1102	\reimp
1103	*/
1104	QModelIndex QListView::indexAt(const QPoint &p) const
1105	{
1106	Q_D(const QListView);
1107	QRect rect(p.x() + horizontalOffset(), p.y() + verticalOffset(), 1, 1);
1108	const QList<QModelIndex> intersectVector = d->intersectingSet(area: rect);
1109	QModelIndex index = intersectVector.size() > 0
1110	? intersectVector.last() : QModelIndex();
1111	if (index.isValid() && visualRect(index).contains(p))
1112	return index;
1113	return QModelIndex();
1114	}
1115
1116	/*!
1117	\reimp
1118	*/
1119	int QListView::horizontalOffset() const
1120	{
1121	return d_func()->commonListView->horizontalOffset();
1122	}
1123
1124	/*!
1125	\reimp
1126	*/
1127	int QListView::verticalOffset() const
1128	{
1129	return d_func()->commonListView->verticalOffset();
1130	}
1131
1132	/*!
1133	\reimp
1134	*/
1135	QModelIndex QListView::moveCursor(CursorAction cursorAction, Qt::KeyboardModifiers modifiers)
1136	{
1137	Q_D(QListView);
1138	Q_UNUSED(modifiers);
1139
1140	auto findAvailableRowBackward = [d](int row) {
1141	while (row >= 0 && d->isHiddenOrDisabled(row))
1142	--row;
1143	return row;
1144	};
1145
1146	auto findAvailableRowForward = [d](int row) {
1147	int rowCount = d->model->rowCount(parent: d->root);
1148	if (!rowCount)
1149	return -1;
1150	while (row < rowCount && d->isHiddenOrDisabled(row))
1151	++row;
1152	if (row >= rowCount)
1153	return -1;
1154	return row;
1155	};
1156
1157	QModelIndex current = currentIndex();
1158	if (!current.isValid()) {
1159	int row = findAvailableRowForward(0);
1160	if (row == -1)
1161	return QModelIndex();
1162	return d->model->index(row, column: d->column, parent: d->root);
1163	}
1164
1165	if ((d->flow == LeftToRight && cursorAction == MoveLeft) ||
1166	(d->flow == TopToBottom && (cursorAction == MoveUp || cursorAction == MovePrevious))) {
1167	const int row = findAvailableRowBackward(current.row() - 1);
1168	if (row == -1)
1169	return current;
1170	return d->model->index(row, column: d->column, parent: d->root);
1171	} else if ((d->flow == LeftToRight && cursorAction == MoveRight) ||
1172	(d->flow == TopToBottom && (cursorAction == MoveDown || cursorAction == MoveNext))) {
1173	const int row = findAvailableRowForward(current.row() + 1);
1174	if (row == -1)
1175	return current;
1176	return d->model->index(row, column: d->column, parent: d->root);
1177	}
1178
1179	const QRect initialRect = rectForIndex(index: current);
1180	QRect rect = initialRect;
1181	if (rect.isEmpty()) {
1182	return d->model->index(row: 0, column: d->column, parent: d->root);
1183	}
1184	if (d->gridSize().isValid()) rect.setSize(d->gridSize());
1185
1186	QSize contents = d->contentsSize();
1187	QList<QModelIndex> intersectVector;
1188
1189	switch (cursorAction) {
1190	case MoveLeft:
1191	while (intersectVector.isEmpty()) {
1192	rect.translate(dx: -rect.width(), dy: 0);
1193	if (rect.right() <= 0)
1194	return current;
1195	if (rect.left() < 0)
1196	rect.setLeft(0);
1197	intersectVector = d->intersectingSet(area: rect);
1198	d->removeCurrentAndDisabled(indexes: &intersectVector, current);
1199	}
1200	return d->closestIndex(target: initialRect, candidates: intersectVector);
1201	case MoveRight:
1202	while (intersectVector.isEmpty()) {
1203	rect.translate(dx: rect.width(), dy: 0);
1204	if (rect.left() >= contents.width())
1205	return current;
1206	if (rect.right() > contents.width())
1207	rect.setRight(contents.width());
1208	intersectVector = d->intersectingSet(area: rect);
1209	d->removeCurrentAndDisabled(indexes: &intersectVector, current);
1210	}
1211	return d->closestIndex(target: initialRect, candidates: intersectVector);
1212	case MovePageUp: {
1213	if (rect.height() >= d->viewport->height())
1214	return moveCursor(cursorAction: QAbstractItemView::MoveUp, modifiers);
1215
1216	rect.moveTop(pos: rect.top() - d->viewport->height() + 1);
1217	if (rect.top() < rect.height()) {
1218	rect.setTop(0);
1219	rect.setBottom(1);
1220	}
1221	QModelIndex findindex = current;
1222	while (intersectVector.isEmpty()
1223	|| rectForIndex(index: findindex).top() <= (rectForIndex(index: current).bottom() - d->viewport->rect().height())
1224	|| rect.top() <= 0) {
1225	rect.translate(dx: 0, dy: 1);
1226	if (rect.bottom() <= 0) {
1227	return current;
1228	}
1229	intersectVector = d->intersectingSet(area: rect);
1230	findindex = d->closestIndex(target: initialRect, candidates: intersectVector);
1231	}
1232	return findindex;
1233	}
1234	case MovePrevious:
1235	case MoveUp:
1236	while (intersectVector.isEmpty()) {
1237	rect.translate(dx: 0, dy: -rect.height());
1238	if (rect.bottom() <= 0) {
1239	#ifdef QT_KEYPAD_NAVIGATION
1240	if (QApplicationPrivate::keypadNavigationEnabled()) {
1241	int row = d->batchStartRow() - 1;
1242	while (row >= 0 && d->isHiddenOrDisabled(row))
1243	--row;
1244	if (row >= 0)
1245	return d->model->index(row, d->column, d->root);
1246	}
1247	#endif
1248	return current;
1249	}
1250	if (rect.top() < 0)
1251	rect.setTop(0);
1252	intersectVector = d->intersectingSet(area: rect);
1253	d->removeCurrentAndDisabled(indexes: &intersectVector, current);
1254	}
1255	return d->closestIndex(target: initialRect, candidates: intersectVector);
1256	case MovePageDown: {
1257	if (rect.height() >= d->viewport->height())
1258	return moveCursor(cursorAction: QAbstractItemView::MoveDown, modifiers);
1259
1260	rect.moveTop(pos: rect.top() + d->viewport->height() - 1);
1261	if (rect.bottom() > contents.height() - rect.height()) {
1262	rect.setTop(contents.height() - 1);
1263	rect.setBottom(contents.height());
1264	}
1265	QModelIndex index = current;
1266	// index's bottom() - current's top() always <= (d->viewport->rect().height()
1267	while (intersectVector.isEmpty()
1268	|| rectForIndex(index).bottom() >= (d->viewport->rect().height() + rectForIndex(index: current).top())
1269	|| rect.bottom() > contents.height()) {
1270	rect.translate(dx: 0, dy: -1);
1271	if (rect.top() >= contents.height()) {
1272	return current;
1273	}
1274	intersectVector = d->intersectingSet(area: rect);
1275	index = d->closestIndex(target: initialRect, candidates: intersectVector);
1276	}
1277	return index;
1278	}
1279	case MoveNext:
1280	case MoveDown:
1281	while (intersectVector.isEmpty()) {
1282	rect.translate(dx: 0, dy: rect.height());
1283	if (rect.top() >= contents.height()) {
1284	#ifdef QT_KEYPAD_NAVIGATION
1285	if (QApplicationPrivate::keypadNavigationEnabled()) {
1286	int rowCount = d->model->rowCount(d->root);
1287	int row = 0;
1288	while (row < rowCount && d->isHiddenOrDisabled(row))
1289	++row;
1290	if (row < rowCount)
1291	return d->model->index(row, d->column, d->root);
1292	}
1293	#endif
1294	return current;
1295	}
1296	if (rect.bottom() > contents.height())
1297	rect.setBottom(contents.height());
1298	intersectVector = d->intersectingSet(area: rect);
1299	d->removeCurrentAndDisabled(indexes: &intersectVector, current);
1300	}
1301	return d->closestIndex(target: initialRect, candidates: intersectVector);
1302	case MoveHome:
1303	return d->model->index(row: 0, column: d->column, parent: d->root);
1304	case MoveEnd:
1305	return d->model->index(row: d->batchStartRow() - 1, column: d->column, parent: d->root);}
1306
1307	return current;
1308	}
1309
1310	/*!
1311	Returns the rectangle of the item at position \a index in the
1312	model. The rectangle is in contents coordinates.
1313
1314	\sa visualRect()
1315	*/
1316	QRect QListView::rectForIndex(const QModelIndex &index) const
1317	{
1318	return d_func()->rectForIndex(index);
1319	}
1320
1321	/*!
1322	\since 4.1
1323
1324	Sets the contents position of the item at \a index in the model to the given
1325	\a position.
1326	If the list view's movement mode is Static or its view mode is ListView,
1327	this function will have no effect.
1328	*/
1329	void QListView::setPositionForIndex(const QPoint &position, const QModelIndex &index)
1330	{
1331	Q_D(QListView);
1332	if (d->movement == Static
1333	|| !d->isIndexValid(index)
1334	|| index.parent() != d->root
1335	|| index.column() != d->column)
1336	return;
1337
1338	d->executePostedLayout();
1339	d->commonListView->setPositionForIndex(position, index);
1340	}
1341
1342	/*!
1343	\reimp
1344	*/
1345	void QListView::setSelection(const QRect &rect, QItemSelectionModel::SelectionFlags command)
1346	{
1347	Q_D(QListView);
1348	if (!d->selectionModel)
1349	return;
1350
1351	// if we are wrapping, we can only select inside the contents rectangle
1352	int w = qMax(a: d->contentsSize().width(), b: d->viewport->width());
1353	int h = qMax(a: d->contentsSize().height(), b: d->viewport->height());
1354	if (d->wrap && !QRect(0, 0, w, h).intersects(r: rect))
1355	return;
1356
1357	QItemSelection selection;
1358
1359	if (rect.width() == 1 && rect.height() == 1) {
1360	const QList<QModelIndex> intersectVector =
1361	d->intersectingSet(area: rect.translated(dx: horizontalOffset(), dy: verticalOffset()));
1362	QModelIndex tl;
1363	if (!intersectVector.isEmpty())
1364	tl = intersectVector.last(); // special case for mouse press; only select the top item
1365	if (tl.isValid() && d->isIndexEnabled(index: tl))
1366	selection.select(topLeft: tl, bottomRight: tl);
1367	} else {
1368	if (state() == DragSelectingState) { // visual selection mode (rubberband selection)
1369	selection = d->selection(rect: rect.translated(dx: horizontalOffset(), dy: verticalOffset()));
1370	} else { // logical selection mode (key and mouse click selection)
1371	QModelIndex tl, br;
1372	// get the first item
1373	const QRect topLeft(rect.left() + horizontalOffset(), rect.top() + verticalOffset(), 1, 1);
1374	QList<QModelIndex> intersectVector = d->intersectingSet(area: topLeft);
1375	if (!intersectVector.isEmpty())
1376	tl = intersectVector.last();
1377	// get the last item
1378	const QRect bottomRight(rect.right() + horizontalOffset(), rect.bottom() + verticalOffset(), 1, 1);
1379	intersectVector = d->intersectingSet(area: bottomRight);
1380	if (!intersectVector.isEmpty())
1381	br = intersectVector.last();
1382
1383	// get the ranges
1384	if (tl.isValid() && br.isValid()
1385	&& d->isIndexEnabled(index: tl)
1386	&& d->isIndexEnabled(index: br)) {
1387	QRect first = d->cellRectForIndex(index: tl);
1388	QRect last = d->cellRectForIndex(index: br);
1389	QRect middle;
1390	if (d->flow == LeftToRight) {
1391	QRect &top = first;
1392	QRect &bottom = last;
1393	// if bottom is above top, swap them
1394	if (top.center().y() > bottom.center().y()) {
1395	QRect tmp = top;
1396	top = bottom;
1397	bottom = tmp;
1398	}
1399	// if the rect are on different lines, expand
1400	if (top.top() != bottom.top()) {
1401	// top rectangle
1402	if (isRightToLeft())
1403	top.setLeft(0);
1404	else
1405	top.setRight(contentsSize().width());
1406	// bottom rectangle
1407	if (isRightToLeft())
1408	bottom.setRight(contentsSize().width());
1409	else
1410	bottom.setLeft(0);
1411	} else if (top.left() > bottom.right()) {
1412	if (isRightToLeft())
1413	bottom.setLeft(top.right());
1414	else
1415	bottom.setRight(top.left());
1416	} else {
1417	if (isRightToLeft())
1418	top.setLeft(bottom.right());
1419	else
1420	top.setRight(bottom.left());
1421	}
1422	// middle rectangle
1423	if (top.bottom() < bottom.top()) {
1424	if (gridSize().isValid() && !gridSize().isNull())
1425	middle.setTop(top.top() + gridSize().height());
1426	else
1427	middle.setTop(top.bottom() + 1);
1428	middle.setLeft(qMin(a: top.left(), b: bottom.left()));
1429	middle.setBottom(bottom.top() - 1);
1430	middle.setRight(qMax(a: top.right(), b: bottom.right()));
1431	}
1432	} else { // TopToBottom
1433	QRect &left = first;
1434	QRect &right = last;
1435	if (left.center().x() > right.center().x())
1436	qSwap(value1&: left, value2&: right);
1437
1438	int ch = contentsSize().height();
1439	if (left.left() != right.left()) {
1440	// left rectangle
1441	if (isRightToLeft())
1442	left.setTop(0);
1443	else
1444	left.setBottom(ch);
1445
1446	// top rectangle
1447	if (isRightToLeft())
1448	right.setBottom(ch);
1449	else
1450	right.setTop(0);
1451	// only set middle if the
1452	middle.setTop(0);
1453	middle.setBottom(ch);
1454	if (gridSize().isValid() && !gridSize().isNull())
1455	middle.setLeft(left.left() + gridSize().width());
1456	else
1457	middle.setLeft(left.right() + 1);
1458	middle.setRight(right.left() - 1);
1459	} else if (left.bottom() < right.top()) {
1460	left.setBottom(right.top() - 1);
1461	} else {
1462	right.setBottom(left.top() - 1);
1463	}
1464	}
1465
1466	// do the selections
1467	QItemSelection topSelection = d->selection(rect: first);
1468	QItemSelection middleSelection = d->selection(rect: middle);
1469	QItemSelection bottomSelection = d->selection(rect: last);
1470	// merge
1471	selection.merge(other: topSelection, command: QItemSelectionModel::Select);
1472	selection.merge(other: middleSelection, command: QItemSelectionModel::Select);
1473	selection.merge(other: bottomSelection, command: QItemSelectionModel::Select);
1474	}
1475	}
1476	}
1477
1478	d->selectionModel->select(selection, command);
1479	}
1480
1481	/*!
1482	\reimp
1483
1484	Since 4.7, the returned region only contains rectangles intersecting
1485	(or included in) the viewport.
1486	*/
1487	QRegion QListView::visualRegionForSelection(const QItemSelection &selection) const
1488	{
1489	Q_D(const QListView);
1490	// ### NOTE: this is a potential bottleneck in non-static mode
1491	int c = d->column;
1492	QRegion selectionRegion;
1493	const QRect &viewportRect = d->viewport->rect();
1494	for (const auto &elem : selection) {
1495	if (!elem.isValid())
1496	continue;
1497	QModelIndex parent = elem.topLeft().parent();
1498	//we only display the children of the root in a listview
1499	//we're not interested in the other model indexes
1500	if (parent != d->root)
1501	continue;
1502	int t = elem.topLeft().row();
1503	int b = elem.bottomRight().row();
1504	if (d->viewMode == IconMode || d->isWrapping()) { // in non-static mode, we have to go through all selected items
1505	for (int r = t; r <= b; ++r) {
1506	const QRect &rect = visualRect(index: d->model->index(row: r, column: c, parent));
1507	if (viewportRect.intersects(r: rect))
1508	selectionRegion += rect;
1509	}
1510	} else { // in static mode, we can optimize a bit
1511	while (t <= b && d->isHidden(row: t)) ++t;
1512	while (b >= t && d->isHidden(row: b)) --b;
1513	const QModelIndex top = d->model->index(row: t, column: c, parent);
1514	const QModelIndex bottom = d->model->index(row: b, column: c, parent);
1515	QRect rect(visualRect(index: top).topLeft(),
1516	visualRect(index: bottom).bottomRight());
1517	if (viewportRect.intersects(r: rect))
1518	selectionRegion += rect;
1519	}
1520	}
1521
1522	return selectionRegion;
1523	}
1524
1525	/*!
1526	\reimp
1527	*/
1528	QModelIndexList QListView::selectedIndexes() const
1529	{
1530	Q_D(const QListView);
1531	if (!d->selectionModel)
1532	return QModelIndexList();
1533
1534	QModelIndexList viewSelected = d->selectionModel->selectedIndexes();
1535	auto ignorable = [this, d](const QModelIndex &index) {
1536	return index.column() != d->column || index.parent() != d->root || isIndexHidden(index);
1537	};
1538	viewSelected.removeIf(pred: ignorable);
1539	return viewSelected;
1540	}
1541
1542	/*!
1543	\internal
1544
1545	Layout the items according to the flow and wrapping properties.
1546	*/
1547	void QListView::doItemsLayout()
1548	{
1549	Q_D(QListView);
1550	// showing the scroll bars will trigger a resize event,
1551	// so we set the state to expanding to avoid
1552	// triggering another layout
1553	QAbstractItemView::State oldState = state();
1554	setState(ExpandingState);
1555	if (d->model->columnCount(parent: d->root) > 0) { // no columns means no contents
1556	d->resetBatchStartRow();
1557	if (layoutMode() == SinglePass) {
1558	d->doItemsLayout(num: d->model->rowCount(parent: d->root)); // layout everything
1559	} else if (!d->batchLayoutTimer.isActive()) {
1560	if (!d->doItemsLayout(num: d->batchSize)) // layout is done
1561	d->batchLayoutTimer.start(msec: 0, obj: this); // do a new batch as fast as possible
1562	}
1563	} else { // clear the QBspTree generated by the last layout
1564	d->clear();
1565	}
1566	QAbstractItemView::doItemsLayout();
1567	setState(oldState); // restoring the oldState
1568	}
1569
1570	/*!
1571	\reimp
1572	*/
1573	void QListView::updateGeometries()
1574	{
1575	Q_D(QListView);
1576	if (geometry().isEmpty() || d->model->rowCount(parent: d->root) <= 0 || d->model->columnCount(parent: d->root) <= 0) {
1577	horizontalScrollBar()->setRange(min: 0, max: 0);
1578	verticalScrollBar()->setRange(min: 0, max: 0);
1579	} else {
1580	QModelIndex index = d->model->index(row: 0, column: d->column, parent: d->root);
1581	QStyleOptionViewItem option;
1582	initViewItemOption(option: &option);
1583	QSize step = d->itemSize(option, index);
1584	d->commonListView->updateHorizontalScrollBar(step);
1585	d->commonListView->updateVerticalScrollBar(step);
1586	}
1587
1588	QAbstractItemView::updateGeometries();
1589
1590	// if the scroll bars are turned off, we resize the contents to the viewport
1591	if (d->movement == Static && !d->isWrapping()) {
1592	d->layoutChildren(); // we need the viewport size to be updated
1593	if (d->flow == TopToBottom) {
1594	if (horizontalScrollBarPolicy() == Qt::ScrollBarAlwaysOff) {
1595	d->setContentsSize(w: viewport()->width(), h: contentsSize().height());
1596	horizontalScrollBar()->setRange(min: 0, max: 0); // we see all the contents anyway
1597	}
1598	} else { // LeftToRight
1599	if (verticalScrollBarPolicy() == Qt::ScrollBarAlwaysOff) {
1600	d->setContentsSize(w: contentsSize().width(), h: viewport()->height());
1601	verticalScrollBar()->setRange(min: 0, max: 0); // we see all the contents anyway
1602	}
1603	}
1604	}
1605
1606	}
1607
1608	/*!
1609	\reimp
1610	*/
1611	bool QListView::isIndexHidden(const QModelIndex &index) const
1612	{
1613	Q_D(const QListView);
1614	return (d->isHidden(row: index.row())
1615	&& (index.parent() == d->root)
1616	&& index.column() == d->column);
1617	}
1618
1619	/*!
1620	\property QListView::modelColumn
1621	\brief the column in the model that is visible
1622
1623	By default, this property contains 0, indicating that the first
1624	column in the model will be shown.
1625	*/
1626	void QListView::setModelColumn(int column)
1627	{
1628	Q_D(QListView);
1629	if (column < 0 || column >= d->model->columnCount(parent: d->root))
1630	return;
1631	d->column = column;
1632	d->doDelayedItemsLayout();
1633	#if QT_CONFIG(accessibility)
1634	if (QAccessible::isActive()) {
1635	QAccessibleTableModelChangeEvent event(this, QAccessibleTableModelChangeEvent::ModelReset);
1636	QAccessible::updateAccessibility(event: &event);
1637	}
1638	#endif
1639	}
1640
1641	int QListView::modelColumn() const
1642	{
1643	Q_D(const QListView);
1644	return d->column;
1645	}
1646
1647	/*!
1648	\property QListView::uniformItemSizes
1649	\brief whether all items in the listview have the same size
1650	\since 4.1
1651
1652	This property should only be set to true if it is guaranteed that all items
1653	in the view have the same size. This enables the view to do some
1654	optimizations for performance purposes.
1655
1656	By default, this property is \c false.
1657	*/
1658	void QListView::setUniformItemSizes(bool enable)
1659	{
1660	Q_D(QListView);
1661	d->uniformItemSizes = enable;
1662	}
1663
1664	bool QListView::uniformItemSizes() const
1665	{
1666	Q_D(const QListView);
1667	return d->uniformItemSizes;
1668	}
1669
1670	/*!
1671	\property QListView::wordWrap
1672	\brief the item text word-wrapping policy
1673	\since 4.2
1674
1675	If this property is \c true then the item text is wrapped where
1676	necessary at word-breaks; otherwise it is not wrapped at all.
1677	This property is \c false by default.
1678
1679	Please note that even if wrapping is enabled, the cell will not be
1680	expanded to make room for the text. It will print ellipsis for
1681	text that cannot be shown, according to the view's
1682	\l{QAbstractItemView::}{textElideMode}.
1683	*/
1684	void QListView::setWordWrap(bool on)
1685	{
1686	Q_D(QListView);
1687	if (d->wrapItemText == on)
1688	return;
1689	d->wrapItemText = on;
1690	d->doDelayedItemsLayout();
1691	}
1692
1693	bool QListView::wordWrap() const
1694	{
1695	Q_D(const QListView);
1696	return d->wrapItemText;
1697	}
1698
1699	/*!
1700	\property QListView::selectionRectVisible
1701	\brief if the selection rectangle should be visible
1702	\since 4.3
1703
1704	If this property is \c true then the selection rectangle is visible;
1705	otherwise it will be hidden.
1706
1707	\note The selection rectangle will only be visible if the selection mode
1708	is in a mode where more than one item can be selected; i.e., it will not
1709	draw a selection rectangle if the selection mode is
1710	QAbstractItemView::SingleSelection.
1711
1712	By default, this property is \c false.
1713	*/
1714	void QListView::setSelectionRectVisible(bool show)
1715	{
1716	Q_D(QListView);
1717	d->modeProperties |= uint(QListViewPrivate::SelectionRectVisible);
1718	d->setSelectionRectVisible(show);
1719	}
1720
1721	bool QListView::isSelectionRectVisible() const
1722	{
1723	Q_D(const QListView);
1724	return d->isSelectionRectVisible();
1725	}
1726
1727	/*!
1728	\property QListView::itemAlignment
1729	\brief the alignment of each item in its cell
1730	\since 5.12
1731
1732	This is only supported in ListMode with TopToBottom flow
1733	and with wrapping enabled.
1734	The default alignment is 0, which means that an item fills
1735	its cell entirely.
1736	*/
1737	void QListView::setItemAlignment(Qt::Alignment alignment)
1738	{
1739	Q_D(QListView);
1740	if (d->itemAlignment == alignment)
1741	return;
1742	d->itemAlignment = alignment;
1743	if (viewMode() == ListMode && flow() == QListView::TopToBottom && isWrapping())
1744	d->doDelayedItemsLayout();
1745	}
1746
1747	Qt::Alignment QListView::itemAlignment() const
1748	{
1749	Q_D(const QListView);
1750	return d->itemAlignment;
1751	}
1752
1753	/*!
1754	\reimp
1755	*/
1756	bool QListView::event(QEvent *e)
1757	{
1758	return QAbstractItemView::event(event: e);
1759	}
1760
1761	/*
1762	* private object implementation
1763	*/
1764
1765	QListViewPrivate::QListViewPrivate()
1766	: QAbstractItemViewPrivate(),
1767	commonListView(nullptr),
1768	wrap(false),
1769	space(0),
1770	flow(QListView::TopToBottom),
1771	movement(QListView::Static),
1772	resizeMode(QListView::Fixed),
1773	layoutMode(QListView::SinglePass),
1774	viewMode(QListView::ListMode),
1775	modeProperties(0),
1776	column(0),
1777	uniformItemSizes(false),
1778	batchSize(100),
1779	showElasticBand(false),
1780	itemAlignment(Qt::Alignment())
1781	{
1782	}
1783
1784	QListViewPrivate::~QListViewPrivate()
1785	{
1786	delete commonListView;
1787	}
1788
1789	void QListViewPrivate::clear()
1790	{
1791	// initialization of data structs
1792	cachedItemSize = QSize();
1793	commonListView->clear();
1794	}
1795
1796	void QListViewPrivate::prepareItemsLayout()
1797	{
1798	Q_Q(QListView);
1799	clear();
1800
1801	//take the size as if there were scrollbar in order to prevent scrollbar to blink
1802	layoutBounds = QRect(QPoint(), q->maximumViewportSize());
1803
1804	int frameAroundContents = 0;
1805	if (q->style()->styleHint(stylehint: QStyle::SH_ScrollView_FrameOnlyAroundContents)) {
1806	QStyleOption option;
1807	option.initFrom(w: q);
1808	frameAroundContents = q->style()->pixelMetric(metric: QStyle::PM_DefaultFrameWidth, option: &option, widget: q) * 2;
1809	}
1810
1811	// maximumViewportSize() already takes scrollbar into account if policy is
1812	// Qt::ScrollBarAlwaysOn but scrollbar extent must be deduced if policy
1813	// is Qt::ScrollBarAsNeeded
1814	int verticalMargin = (vbarpolicy == Qt::ScrollBarAsNeeded) && (flow == QListView::LeftToRight || vbar->isVisible())
1815	&& !q->style()->pixelMetric(metric: QStyle::PM_ScrollView_ScrollBarOverlap, option: nullptr, widget: vbar)
1816	? q->style()->pixelMetric(metric: QStyle::PM_ScrollBarExtent, option: nullptr, widget: vbar) + frameAroundContents
1817	: 0;
1818	int horizontalMargin = hbarpolicy==Qt::ScrollBarAsNeeded
1819	? q->style()->pixelMetric(metric: QStyle::PM_ScrollBarExtent, option: nullptr, widget: hbar) + frameAroundContents
1820	: 0;
1821
1822	layoutBounds.adjust(dx1: 0, dy1: 0, dx2: -verticalMargin, dy2: -horizontalMargin);
1823
1824	int rowCount = model->columnCount(parent: root) <= 0 ? 0 : model->rowCount(parent: root);
1825	commonListView->setRowCount(rowCount);
1826	}
1827
1828	/*!
1829	\internal
1830	*/
1831	bool QListViewPrivate::doItemsLayout(int delta)
1832	{
1833	int max = model->rowCount(parent: root) - 1;
1834	int first = batchStartRow();
1835	int last = qMin(a: first + delta - 1, b: max);
1836
1837	if (first == 0) {
1838	layoutChildren(); // make sure the viewport has the right size
1839	prepareItemsLayout();
1840	}
1841
1842	if (max < 0 || last < first) {
1843	return true; // nothing to do
1844	}
1845
1846	QListViewLayoutInfo info;
1847	info.bounds = layoutBounds;
1848	info.grid = gridSize();
1849	info.spacing = (info.grid.isValid() ? 0 : spacing());
1850	info.first = first;
1851	info.last = last;
1852	info.wrap = isWrapping();
1853	info.flow = flow;
1854	info.max = max;
1855
1856	return commonListView->doBatchedItemLayout(info, max);
1857	}
1858
1859	QListViewItem QListViewPrivate::indexToListViewItem(const QModelIndex &index) const
1860	{
1861	if (!index.isValid() || isHidden(row: index.row()))
1862	return QListViewItem();
1863
1864	return commonListView->indexToListViewItem(index);
1865	}
1866
1867	QRect QListViewPrivate::mapToViewport(const QRect &rect, bool extend) const
1868	{
1869	Q_Q(const QListView);
1870	if (!rect.isValid())
1871	return rect;
1872
1873	QRect result = extend ? commonListView->mapToViewport(rect) : rect;
1874	int dx = -q->horizontalOffset();
1875	int dy = -q->verticalOffset();
1876	return result.adjusted(xp1: dx, yp1: dy, xp2: dx, yp2: dy);
1877	}
1878
1879	QModelIndex QListViewPrivate::closestIndex(const QRect &target,
1880	const QList<QModelIndex> &candidates) const
1881	{
1882	int distance = 0;
1883	int shortest = INT_MAX;
1884	QModelIndex closest;
1885	QList<QModelIndex>::const_iterator it = candidates.begin();
1886
1887	for (; it != candidates.end(); ++it) {
1888	if (!(*it).isValid())
1889	continue;
1890
1891	const QRect indexRect = indexToListViewItem(index: *it).rect();
1892
1893	//if the center x (or y) position of an item is included in the rect of the other item,
1894	//we define the distance between them as the difference in x (or y) of their respective center.
1895	// Otherwise, we use the nahattan length between the 2 items
1896	if ((target.center().x() >= indexRect.x() && target.center().x() < indexRect.right())
1897	|| (indexRect.center().x() >= target.x() && indexRect.center().x() < target.right())) {
1898	//one item's center is at the vertical of the other
1899	distance = qAbs(t: indexRect.center().y() - target.center().y());
1900	} else if ((target.center().y() >= indexRect.y() && target.center().y() < indexRect.bottom())
1901	|| (indexRect.center().y() >= target.y() && indexRect.center().y() < target.bottom())) {
1902	//one item's center is at the vertical of the other
1903	distance = qAbs(t: indexRect.center().x() - target.center().x());
1904	} else {
1905	distance = (indexRect.center() - target.center()).manhattanLength();
1906	}
1907	if (distance < shortest) {
1908	shortest = distance;
1909	closest = *it;
1910	}
1911	}
1912	return closest;
1913	}
1914
1915	QSize QListViewPrivate::itemSize(const QStyleOptionViewItem &option, const QModelIndex &index) const
1916	{
1917	Q_Q(const QListView);
1918	if (!uniformItemSizes) {
1919	const QAbstractItemDelegate *delegate = q->itemDelegateForIndex(index);
1920	return delegate ? delegate->sizeHint(option, index) : QSize();
1921	}
1922	if (!cachedItemSize.isValid()) { // the last item is probably the largest, so we use its size
1923	int row = model->rowCount(parent: root) - 1;
1924	QModelIndex sample = model->index(row, column, parent: root);
1925	const QAbstractItemDelegate *delegate = q->itemDelegateForIndex(index: sample);
1926	cachedItemSize = delegate ? delegate->sizeHint(option, index: sample) : QSize();
1927	}
1928	return cachedItemSize;
1929	}
1930
1931	QItemSelection QListViewPrivate::selection(const QRect &rect) const
1932	{
1933	QItemSelection selection;
1934	QModelIndex tl, br;
1935	const QList<QModelIndex> intersectVector = intersectingSet(area: rect);
1936	QList<QModelIndex>::const_iterator it = intersectVector.begin();
1937	for (; it != intersectVector.end(); ++it) {
1938	if (!tl.isValid() && !br.isValid()) {
1939	tl = br = *it;
1940	} else if ((*it).row() == (tl.row() - 1)) {
1941	tl = *it; // expand current range
1942	} else if ((*it).row() == (br.row() + 1)) {
1943	br = (*it); // expand current range
1944	} else {
1945	selection.select(topLeft: tl, bottomRight: br); // select current range
1946	tl = br = *it; // start new range
1947	}
1948	}
1949
1950	if (tl.isValid() && br.isValid())
1951	selection.select(topLeft: tl, bottomRight: br);
1952	else if (tl.isValid())
1953	selection.select(topLeft: tl, bottomRight: tl);
1954	else if (br.isValid())
1955	selection.select(topLeft: br, bottomRight: br);
1956
1957	return selection;
1958	}
1959
1960	#if QT_CONFIG(draganddrop)
1961	QAbstractItemView::DropIndicatorPosition QListViewPrivate::position(const QPoint &pos, const QRect &rect, const QModelIndex &idx) const
1962	{
1963	if (viewMode == QListView::ListMode && flow == QListView::LeftToRight)
1964	return static_cast<QListModeViewBase *>(commonListView)->position(pos, rect, idx);
1965	else
1966	return QAbstractItemViewPrivate::position(pos, rect, idx);
1967	}
1968
1969	bool QListViewPrivate::dropOn(QDropEvent *event, int *dropRow, int *dropCol, QModelIndex *dropIndex)
1970	{
1971	if (viewMode == QListView::ListMode && flow == QListView::LeftToRight)
1972	return static_cast<QListModeViewBase *>(commonListView)->dropOn(event, row: dropRow, col: dropCol, index: dropIndex);
1973	else
1974	return QAbstractItemViewPrivate::dropOn(event, row: dropRow, col: dropCol, index: dropIndex);
1975	}
1976	#endif
1977
1978	void QListViewPrivate::removeCurrentAndDisabled(QList<QModelIndex> *indexes,
1979	const QModelIndex &current) const
1980	{
1981	auto isCurrentOrDisabled = [this, current](const QModelIndex &index) {
1982	return !isIndexEnabled(index) || index == current;
1983	};
1984	indexes->removeIf(pred: isCurrentOrDisabled);
1985	}
1986
1987	/*
1988	* Common ListView Implementation
1989	*/
1990
1991	void QCommonListViewBase::appendHiddenRow(int row)
1992	{
1993	dd->hiddenRows.insert(value: dd->model->index(row, column: 0, parent: qq->rootIndex()));
1994	}
1995
1996	void QCommonListViewBase::removeHiddenRow(int row)
1997	{
1998	dd->hiddenRows.remove(value: dd->model->index(row, column: 0, parent: qq->rootIndex()));
1999	}
2000
2001	#if QT_CONFIG(draganddrop)
2002	void QCommonListViewBase::paintDragDrop(QPainter *painter)
2003	{
2004	// FIXME: Until the we can provide a proper drop indicator
2005	// in IconMode, it makes no sense to show it
2006	dd->paintDropIndicator(painter);
2007	}
2008	#endif
2009
2010	QSize QListModeViewBase::viewportSize(const QAbstractItemView *v)
2011	{
2012	return v->contentsRect().marginsRemoved(margins: v->viewportMargins()).size();
2013	}
2014
2015	void QCommonListViewBase::updateHorizontalScrollBar(const QSize &step)
2016	{
2017	horizontalScrollBar()->d_func()->itemviewChangeSingleStep(step: step.width() + spacing());
2018	horizontalScrollBar()->setPageStep(viewport()->width());
2019
2020	// If both scroll bars are set to auto, we might end up in a situation with enough space
2021	// for the actual content. But still one of the scroll bars will become enabled due to
2022	// the other one using the space. The other one will become invisible in the same cycle.
2023	// -> Infinite loop, QTBUG-39902
2024	const bool bothScrollBarsAuto = qq->verticalScrollBarPolicy() == Qt::ScrollBarAsNeeded &&
2025	qq->horizontalScrollBarPolicy() == Qt::ScrollBarAsNeeded;
2026
2027	const QSize viewportSize = QListModeViewBase::viewportSize(v: qq);
2028
2029	bool verticalWantsToShow = contentsSize.height() > viewportSize.height();
2030	bool horizontalWantsToShow;
2031	if (verticalWantsToShow)
2032	horizontalWantsToShow = contentsSize.width() > viewportSize.width() - qq->verticalScrollBar()->width();
2033	else
2034	horizontalWantsToShow = contentsSize.width() > viewportSize.width();
2035
2036	if (bothScrollBarsAuto && !horizontalWantsToShow) {
2037	// break the infinite loop described above by setting the range to 0, 0.
2038	// QAbstractScrollArea will then hide the scroll bar for us
2039	horizontalScrollBar()->setRange(min: 0, max: 0);
2040	} else {
2041	horizontalScrollBar()->setRange(min: 0, max: contentsSize.width() - viewport()->width());
2042	}
2043	}
2044
2045	void QCommonListViewBase::updateVerticalScrollBar(const QSize &step)
2046	{
2047	verticalScrollBar()->d_func()->itemviewChangeSingleStep(step: step.height() + spacing());
2048	verticalScrollBar()->setPageStep(viewport()->height());
2049
2050	// If both scroll bars are set to auto, we might end up in a situation with enough space
2051	// for the actual content. But still one of the scroll bars will become enabled due to
2052	// the other one using the space. The other one will become invisible in the same cycle.
2053	// -> Infinite loop, QTBUG-39902
2054	const bool bothScrollBarsAuto = qq->verticalScrollBarPolicy() == Qt::ScrollBarAsNeeded &&
2055	qq->horizontalScrollBarPolicy() == Qt::ScrollBarAsNeeded;
2056
2057	const QSize viewportSize = QListModeViewBase::viewportSize(v: qq);
2058
2059	bool horizontalWantsToShow = contentsSize.width() > viewportSize.width();
2060	bool verticalWantsToShow;
2061	if (horizontalWantsToShow)
2062	verticalWantsToShow = contentsSize.height() > viewportSize.height() - qq->horizontalScrollBar()->height();
2063	else
2064	verticalWantsToShow = contentsSize.height() > viewportSize.height();
2065
2066	if (bothScrollBarsAuto && !verticalWantsToShow) {
2067	// break the infinite loop described above by setting the range to 0, 0.
2068	// QAbstractScrollArea will then hide the scroll bar for us
2069	verticalScrollBar()->setRange(min: 0, max: 0);
2070	} else {
2071	verticalScrollBar()->setRange(min: 0, max: contentsSize.height() - viewport()->height());
2072	}
2073	}
2074
2075	void QCommonListViewBase::scrollContentsBy(int dx, int dy, bool /*scrollElasticBand*/)
2076	{
2077	dd->scrollContentsBy(dx: isRightToLeft() ? -dx : dx, dy);
2078	}
2079
2080	int QCommonListViewBase::verticalScrollToValue(int /*index*/, QListView::ScrollHint hint,
2081	bool above, bool below, const QRect &area, const QRect &rect) const
2082	{
2083	int verticalValue = verticalScrollBar()->value();
2084	QRect adjusted = rect.adjusted(xp1: -spacing(), yp1: -spacing(), xp2: spacing(), yp2: spacing());
2085	if (hint == QListView::PositionAtTop || above)
2086	verticalValue += adjusted.top();
2087	else if (hint == QListView::PositionAtBottom || below)
2088	verticalValue += qMin(a: adjusted.top(), b: adjusted.bottom() - area.height() + 1);
2089	else if (hint == QListView::PositionAtCenter)
2090	verticalValue += adjusted.top() - ((area.height() - adjusted.height()) / 2);
2091	return verticalValue;
2092	}
2093
2094	int QCommonListViewBase::horizontalOffset() const
2095	{
2096	return (isRightToLeft() ? horizontalScrollBar()->maximum() - horizontalScrollBar()->value() : horizontalScrollBar()->value());
2097	}
2098
2099	int QCommonListViewBase::horizontalScrollToValue(const int /*index*/, QListView::ScrollHint hint,
2100	bool leftOf, bool rightOf, const QRect &area, const QRect &rect) const
2101	{
2102	int horizontalValue = horizontalScrollBar()->value();
2103	if (isRightToLeft()) {
2104	if (hint == QListView::PositionAtCenter) {
2105	horizontalValue += ((area.width() - rect.width()) / 2) - rect.left();
2106	} else {
2107	if (leftOf)
2108	horizontalValue -= rect.left();
2109	else if (rightOf)
2110	horizontalValue += qMin(a: rect.left(), b: area.width() - rect.right());
2111	}
2112	} else {
2113	if (hint == QListView::PositionAtCenter) {
2114	horizontalValue += rect.left() - ((area.width()- rect.width()) / 2);
2115	} else {
2116	if (leftOf)
2117	horizontalValue += rect.left();
2118	else if (rightOf)
2119	horizontalValue += qMin(a: rect.left(), b: rect.right() - area.width());
2120	}
2121	}
2122	return horizontalValue;
2123	}
2124
2125	/*
2126	* ListMode ListView Implementation
2127	*/
2128	QListModeViewBase::QListModeViewBase(QListView *q, QListViewPrivate *d)
2129	: QCommonListViewBase(q, d)
2130	{
2131	#if QT_CONFIG(draganddrop)
2132	dd->defaultDropAction = Qt::CopyAction;
2133	#endif
2134	}
2135
2136	#if QT_CONFIG(draganddrop)
2137	QAbstractItemView::DropIndicatorPosition QListModeViewBase::position(const QPoint &pos, const QRect &rect, const QModelIndex &index) const
2138	{
2139	QAbstractItemView::DropIndicatorPosition r = QAbstractItemView::OnViewport;
2140	if (!dd->overwrite) {
2141	const int margin = 2;
2142	if (pos.x() - rect.left() < margin) {
2143	r = QAbstractItemView::AboveItem; // Visually, on the left
2144	} else if (rect.right() - pos.x() < margin) {
2145	r = QAbstractItemView::BelowItem; // Visually, on the right
2146	} else if (rect.contains(p: pos, proper: true)) {
2147	r = QAbstractItemView::OnItem;
2148	}
2149	} else {
2150	QRect touchingRect = rect;
2151	touchingRect.adjust(dx1: -1, dy1: -1, dx2: 1, dy2: 1);
2152	if (touchingRect.contains(p: pos, proper: false)) {
2153	r = QAbstractItemView::OnItem;
2154	}
2155	}
2156
2157	if (r == QAbstractItemView::OnItem && (!(dd->model->flags(index) & Qt::ItemIsDropEnabled)))
2158	r = pos.x() < rect.center().x() ? QAbstractItemView::AboveItem : QAbstractItemView::BelowItem;
2159
2160	return r;
2161	}
2162
2163	void QListModeViewBase::dragMoveEvent(QDragMoveEvent *event)
2164	{
2165	if (qq->dragDropMode() == QAbstractItemView::InternalMove
2166	&& (event->source() != qq || !(event->possibleActions() & Qt::MoveAction)))
2167	return;
2168
2169	// ignore by default
2170	event->ignore();
2171
2172	// can't use indexAt, doesn't account for spacing.
2173	QPoint p = event->position().toPoint();
2174	QRect rect(p.x() + horizontalOffset(), p.y() + verticalOffset(), 1, 1);
2175	rect.adjust(dx1: -dd->spacing(), dy1: -dd->spacing(), dx2: dd->spacing(), dy2: dd->spacing());
2176	const QList<QModelIndex> intersectVector = dd->intersectingSet(area: rect);
2177	QModelIndex index = intersectVector.size() > 0
2178	? intersectVector.last() : QModelIndex();
2179	dd->hover = index;
2180	if (!dd->droppingOnItself(event, index)
2181	&& dd->canDrop(event)) {
2182
2183	if (index.isValid() && dd->showDropIndicator) {
2184	QRect rect = qq->visualRect(index);
2185	dd->dropIndicatorPosition = position(pos: event->position().toPoint(), rect, index);
2186	// if spacing, should try to draw between items, not just next to item.
2187	switch (dd->dropIndicatorPosition) {
2188	case QAbstractItemView::AboveItem:
2189	if (dd->isIndexDropEnabled(index: index.parent())) {
2190	dd->dropIndicatorRect = QRect(rect.left()-dd->spacing(), rect.top(), 0, rect.height());
2191	event->accept();
2192	} else {
2193	dd->dropIndicatorRect = QRect();
2194	}
2195	break;
2196	case QAbstractItemView::BelowItem:
2197	if (dd->isIndexDropEnabled(index: index.parent())) {
2198	dd->dropIndicatorRect = QRect(rect.right()+dd->spacing(), rect.top(), 0, rect.height());
2199	event->accept();
2200	} else {
2201	dd->dropIndicatorRect = QRect();
2202	}
2203	break;
2204	case QAbstractItemView::OnItem:
2205	if (dd->isIndexDropEnabled(index)) {
2206	dd->dropIndicatorRect = rect;
2207	event->accept();
2208	} else {
2209	dd->dropIndicatorRect = QRect();
2210	}
2211	break;
2212	case QAbstractItemView::OnViewport:
2213	dd->dropIndicatorRect = QRect();
2214	if (dd->isIndexDropEnabled(index: qq->rootIndex())) {
2215	event->accept(); // allow dropping in empty areas
2216	}
2217	break;
2218	}
2219	} else {
2220	dd->dropIndicatorRect = QRect();
2221	dd->dropIndicatorPosition = QAbstractItemView::OnViewport;
2222	if (dd->isIndexDropEnabled(index: qq->rootIndex())) {
2223	event->accept(); // allow dropping in empty areas
2224	}
2225	}
2226	dd->viewport->update();
2227	} // can drop
2228
2229	if (dd->shouldAutoScroll(pos: event->position().toPoint()))
2230	qq->startAutoScroll();
2231	}
2232
2233	/*!
2234	If the event hasn't already been accepted, determines the index to drop on.
2235
2236	if (row == -1 && col == -1)
2237	// append to this drop index
2238	else
2239	// place at row, col in drop index
2240
2241	If it returns \c true a drop can be done, and dropRow, dropCol and dropIndex reflects the position of the drop.
2242	\internal
2243	*/
2244	bool QListModeViewBase::dropOn(QDropEvent *event, int *dropRow, int *dropCol, QModelIndex *dropIndex)
2245	{
2246	if (event->isAccepted())
2247	return false;
2248
2249	QModelIndex index;
2250	if (dd->viewport->rect().contains(p: event->position().toPoint())) {
2251	// can't use indexAt, doesn't account for spacing.
2252	QPoint p = event->position().toPoint();
2253	QRect rect(p.x() + horizontalOffset(), p.y() + verticalOffset(), 1, 1);
2254	rect.adjust(dx1: -dd->spacing(), dy1: -dd->spacing(), dx2: dd->spacing(), dy2: dd->spacing());
2255	const QList<QModelIndex> intersectVector = dd->intersectingSet(area: rect);
2256	index = intersectVector.size() > 0
2257	? intersectVector.last() : QModelIndex();
2258	if (!index.isValid())
2259	index = dd->root;
2260	}
2261
2262	// If we are allowed to do the drop
2263	if (dd->model->supportedDropActions() & event->dropAction()) {
2264	int row = -1;
2265	int col = -1;
2266	if (index != dd->root) {
2267	dd->dropIndicatorPosition = position(pos: event->position().toPoint(), rect: qq->visualRect(index), index);
2268	switch (dd->dropIndicatorPosition) {
2269	case QAbstractItemView::AboveItem:
2270	row = index.row();
2271	col = index.column();
2272	index = index.parent();
2273	break;
2274	case QAbstractItemView::BelowItem:
2275	row = index.row() + 1;
2276	col = index.column();
2277	index = index.parent();
2278	break;
2279	case QAbstractItemView::OnItem:
2280	case QAbstractItemView::OnViewport:
2281	break;
2282	}
2283	} else {
2284	dd->dropIndicatorPosition = QAbstractItemView::OnViewport;
2285	}
2286	*dropIndex = index;
2287	*dropRow = row;
2288	*dropCol = col;
2289	if (!dd->droppingOnItself(event, index))
2290	return true;
2291	}
2292	return false;
2293	}
2294
2295	#endif //QT_CONFIG(draganddrop)
2296
2297	void QListModeViewBase::updateVerticalScrollBar(const QSize &step)
2298	{
2299	if (verticalScrollMode() == QAbstractItemView::ScrollPerItem
2300	&& ((flow() == QListView::TopToBottom && !isWrapping())
2301	|| (flow() == QListView::LeftToRight && isWrapping()))) {
2302	const int steps = (flow() == QListView::TopToBottom ? scrollValueMap : segmentPositions).size() - 1;
2303	if (steps > 0) {
2304	const int pageSteps = perItemScrollingPageSteps(length: viewport()->height(), bounds: contentsSize.height(), wrap: isWrapping());
2305	verticalScrollBar()->setSingleStep(1);
2306	verticalScrollBar()->setPageStep(pageSteps);
2307	verticalScrollBar()->setRange(min: 0, max: steps - pageSteps);
2308	} else {
2309	verticalScrollBar()->setRange(min: 0, max: 0);
2310	}
2311	// } else if (vertical && d->isWrapping() && d->movement == Static) {
2312	// ### wrapped scrolling in flow direction
2313	} else {
2314	QCommonListViewBase::updateVerticalScrollBar(step);
2315	}
2316	}
2317
2318	void QListModeViewBase::updateHorizontalScrollBar(const QSize &step)
2319	{
2320	if (horizontalScrollMode() == QAbstractItemView::ScrollPerItem
2321	&& ((flow() == QListView::TopToBottom && isWrapping())
2322	|| (flow() == QListView::LeftToRight && !isWrapping()))) {
2323	int steps = (flow() == QListView::TopToBottom ? segmentPositions : scrollValueMap).size() - 1;
2324	if (steps > 0) {
2325	const int pageSteps = perItemScrollingPageSteps(length: viewport()->width(), bounds: contentsSize.width(), wrap: isWrapping());
2326	horizontalScrollBar()->setSingleStep(1);
2327	horizontalScrollBar()->setPageStep(pageSteps);
2328	horizontalScrollBar()->setRange(min: 0, max: steps - pageSteps);
2329	} else {
2330	horizontalScrollBar()->setRange(min: 0, max: 0);
2331	}
2332	} else {
2333	QCommonListViewBase::updateHorizontalScrollBar(step);
2334	}
2335	}
2336
2337	int QListModeViewBase::verticalScrollToValue(int index, QListView::ScrollHint hint,
2338	bool above, bool below, const QRect &area, const QRect &rect) const
2339	{
2340	if (verticalScrollMode() == QAbstractItemView::ScrollPerItem) {
2341	int value;
2342	if (scrollValueMap.isEmpty()) {
2343	value = 0;
2344	} else {
2345	int scrollBarValue = verticalScrollBar()->value();
2346	int numHidden = 0;
2347	for (const auto &idx : std::as_const(t&: dd->hiddenRows))
2348	if (idx.row() <= scrollBarValue)
2349	++numHidden;
2350	value = qBound(min: 0, val: scrollValueMap.at(i: verticalScrollBar()->value()) - numHidden, max: flowPositions.size() - 1);
2351	}
2352	if (above)
2353	hint = QListView::PositionAtTop;
2354	else if (below)
2355	hint = QListView::PositionAtBottom;
2356	if (hint == QListView::EnsureVisible)
2357	return value;
2358
2359	return perItemScrollToValue(index, value, height: area.height(), hint, orientation: Qt::Vertical, wrap: isWrapping(), extent: rect.height());
2360	}
2361
2362	return QCommonListViewBase::verticalScrollToValue(index, hint, above, below, area, rect);
2363	}
2364
2365	int QListModeViewBase::horizontalOffset() const
2366	{
2367	if (horizontalScrollMode() == QAbstractItemView::ScrollPerItem) {
2368	if (isWrapping()) {
2369	if (flow() == QListView::TopToBottom && !segmentPositions.isEmpty()) {
2370	const int max = segmentPositions.size() - 1;
2371	int currentValue = qBound(min: 0, val: horizontalScrollBar()->value(), max);
2372	int position = segmentPositions.at(i: currentValue);
2373	int maximumValue = qBound(min: 0, val: horizontalScrollBar()->maximum(), max);
2374	int maximum = segmentPositions.at(i: maximumValue);
2375	return (isRightToLeft() ? maximum - position : position);
2376	}
2377	} else if (flow() == QListView::LeftToRight && !flowPositions.isEmpty()) {
2378	int position = flowPositions.at(i: scrollValueMap.at(i: horizontalScrollBar()->value()));
2379	int maximum = flowPositions.at(i: scrollValueMap.at(i: horizontalScrollBar()->maximum()));
2380	return (isRightToLeft() ? maximum - position : position);
2381	}
2382	}
2383	return QCommonListViewBase::horizontalOffset();
2384	}
2385
2386	int QListModeViewBase::verticalOffset() const
2387	{
2388	if (verticalScrollMode() == QAbstractItemView::ScrollPerItem) {
2389	if (isWrapping()) {
2390	if (flow() == QListView::LeftToRight && !segmentPositions.isEmpty()) {
2391	int value = verticalScrollBar()->value();
2392	if (value >= segmentPositions.size())
2393	return 0;
2394	return segmentPositions.at(i: value) - spacing();
2395	}
2396	} else if (flow() == QListView::TopToBottom && !flowPositions.isEmpty()) {
2397	int value = verticalScrollBar()->value();
2398	if (value > scrollValueMap.size())
2399	return 0;
2400	return flowPositions.at(i: scrollValueMap.at(i: value)) - spacing();
2401	}
2402	}
2403	return QCommonListViewBase::verticalOffset();
2404	}
2405
2406	int QListModeViewBase::horizontalScrollToValue(int index, QListView::ScrollHint hint,
2407	bool leftOf, bool rightOf, const QRect &area, const QRect &rect) const
2408	{
2409	if (horizontalScrollMode() != QAbstractItemView::ScrollPerItem)
2410	return QCommonListViewBase::horizontalScrollToValue(index, hint, leftOf, rightOf, area, rect);
2411
2412	int value;
2413	if (scrollValueMap.isEmpty())
2414	value = 0;
2415	else
2416	value = qBound(min: 0, val: scrollValueMap.at(i: horizontalScrollBar()->value()), max: flowPositions.size() - 1);
2417	if (leftOf)
2418	hint = QListView::PositionAtTop;
2419	else if (rightOf)
2420	hint = QListView::PositionAtBottom;
2421	if (hint == QListView::EnsureVisible)
2422	return value;
2423
2424	return perItemScrollToValue(index, value, height: area.width(), hint, orientation: Qt::Horizontal, wrap: isWrapping(), extent: rect.width());
2425	}
2426
2427	void QListModeViewBase::scrollContentsBy(int dx, int dy, bool scrollElasticBand)
2428	{
2429	// ### reorder this logic
2430	const int verticalValue = verticalScrollBar()->value();
2431	const int horizontalValue = horizontalScrollBar()->value();
2432	const bool vertical = (verticalScrollMode() == QAbstractItemView::ScrollPerItem);
2433	const bool horizontal = (horizontalScrollMode() == QAbstractItemView::ScrollPerItem);
2434
2435	if (isWrapping()) {
2436	if (segmentPositions.isEmpty())
2437	return;
2438	const int max = segmentPositions.size() - 1;
2439	if (horizontal && flow() == QListView::TopToBottom && dx != 0) {
2440	int currentValue = qBound(min: 0, val: horizontalValue, max);
2441	int previousValue = qBound(min: 0, val: currentValue + dx, max);
2442	int currentCoordinate = segmentPositions.at(i: currentValue) - spacing();
2443	int previousCoordinate = segmentPositions.at(i: previousValue) - spacing();
2444	dx = previousCoordinate - currentCoordinate;
2445	} else if (vertical && flow() == QListView::LeftToRight && dy != 0) {
2446	int currentValue = qBound(min: 0, val: verticalValue, max);
2447	int previousValue = qBound(min: 0, val: currentValue + dy, max);
2448	int currentCoordinate = segmentPositions.at(i: currentValue) - spacing();
2449	int previousCoordinate = segmentPositions.at(i: previousValue) - spacing();
2450	dy = previousCoordinate - currentCoordinate;
2451	}
2452	} else {
2453	if (flowPositions.isEmpty())
2454	return;
2455	const int max = scrollValueMap.size() - 1;
2456	if (vertical && flow() == QListView::TopToBottom && dy != 0) {
2457	int currentValue = qBound(min: 0, val: verticalValue, max);
2458	int previousValue = qBound(min: 0, val: currentValue + dy, max);
2459	int currentCoordinate = flowPositions.at(i: scrollValueMap.at(i: currentValue));
2460	int previousCoordinate = flowPositions.at(i: scrollValueMap.at(i: previousValue));
2461	dy = previousCoordinate - currentCoordinate;
2462	} else if (horizontal && flow() == QListView::LeftToRight && dx != 0) {
2463	int currentValue = qBound(min: 0, val: horizontalValue, max);
2464	int previousValue = qBound(min: 0, val: currentValue + dx, max);
2465	int currentCoordinate = flowPositions.at(i: scrollValueMap.at(i: currentValue));
2466	int previousCoordinate = flowPositions.at(i: scrollValueMap.at(i: previousValue));
2467	dx = previousCoordinate - currentCoordinate;
2468	}
2469	}
2470	QCommonListViewBase::scrollContentsBy(dx, dy, scrollElasticBand);
2471	}
2472
2473	bool QListModeViewBase::doBatchedItemLayout(const QListViewLayoutInfo &info, int max)
2474	{
2475	doStaticLayout(info);
2476	return batchStartRow > max; // returning true stops items layout
2477	}
2478
2479	QListViewItem QListModeViewBase::indexToListViewItem(const QModelIndex &index) const
2480	{
2481	if (flowPositions.isEmpty()
2482	|| segmentPositions.isEmpty()
2483	|| index.row() >= flowPositions.size() - 1)
2484	return QListViewItem();
2485
2486	const int segment = qBinarySearch<int>(vec: segmentStartRows, item: index.row(),
2487	start: 0, end: segmentStartRows.size() - 1);
2488
2489
2490	QStyleOptionViewItem options;
2491	initViewItemOption(option: &options);
2492	options.rect.setSize(contentsSize);
2493	QSize size = (uniformItemSizes() && cachedItemSize().isValid())
2494	? cachedItemSize() : itemSize(opt: options, idx: index);
2495	QSize cellSize = size;
2496
2497	QPoint pos;
2498	if (flow() == QListView::LeftToRight) {
2499	pos.setX(flowPositions.at(i: index.row()));
2500	pos.setY(segmentPositions.at(i: segment));
2501	} else { // TopToBottom
2502	pos.setY(flowPositions.at(i: index.row()));
2503	pos.setX(segmentPositions.at(i: segment));
2504	if (isWrapping()) { // make the items as wide as the segment
2505	int right = (segment + 1 >= segmentPositions.size()
2506	? contentsSize.width()
2507	: segmentPositions.at(i: segment + 1));
2508	cellSize.setWidth(right - pos.x());
2509	} else { // make the items as wide as the viewport
2510	cellSize.setWidth(qMax(a: size.width(), b: viewport()->width() - 2 * spacing()));
2511	}
2512	}
2513
2514	if (dd->itemAlignment & Qt::AlignHorizontal_Mask) {
2515	size.setWidth(qMin(a: size.width(), b: cellSize.width()));
2516	if (dd->itemAlignment & Qt::AlignRight)
2517	pos.setX(pos.x() + cellSize.width() - size.width());
2518	if (dd->itemAlignment & Qt::AlignHCenter)
2519	pos.setX(pos.x() + (cellSize.width() - size.width()) / 2);
2520	} else {
2521	size.setWidth(cellSize.width());
2522	}
2523
2524	return QListViewItem(QRect(pos, size), index.row());
2525	}
2526
2527	QPoint QListModeViewBase::initStaticLayout(const QListViewLayoutInfo &info)
2528	{
2529	int x, y;
2530	if (info.first == 0) {
2531	flowPositions.clear();
2532	segmentPositions.clear();
2533	segmentStartRows.clear();
2534	segmentExtents.clear();
2535	scrollValueMap.clear();
2536	x = info.bounds.left() + info.spacing;
2537	y = info.bounds.top() + info.spacing;
2538	segmentPositions.append(t: info.flow == QListView::LeftToRight ? y : x);
2539	segmentStartRows.append(t: 0);
2540	} else if (info.wrap) {
2541	if (info.flow == QListView::LeftToRight) {
2542	x = batchSavedPosition;
2543	y = segmentPositions.constLast();
2544	} else { // flow == QListView::TopToBottom
2545	x = segmentPositions.constLast();
2546	y = batchSavedPosition;
2547	}
2548	} else { // not first and not wrap
2549	if (info.flow == QListView::LeftToRight) {
2550	x = batchSavedPosition;
2551	y = info.bounds.top() + info.spacing;
2552	} else { // flow == QListView::TopToBottom
2553	x = info.bounds.left() + info.spacing;
2554	y = batchSavedPosition;
2555	}
2556	}
2557	return QPoint(x, y);
2558	}
2559
2560	/*!
2561	\internal
2562	*/
2563	void QListModeViewBase::doStaticLayout(const QListViewLayoutInfo &info)
2564	{
2565	const bool useItemSize = !info.grid.isValid();
2566	const QPoint topLeft = initStaticLayout(info);
2567	QStyleOptionViewItem option;
2568	initViewItemOption(option: &option);
2569	option.rect = info.bounds;
2570	option.rect.adjust(dx1: info.spacing, dy1: info.spacing, dx2: -info.spacing, dy2: -info.spacing);
2571
2572	// The static layout data structures are as follows:
2573	// One vector contains the coordinate in the direction of layout flow.
2574	// Another vector contains the coordinates of the segments.
2575	// A third vector contains the index (model row) of the first item
2576	// of each segment.
2577
2578	int segStartPosition;
2579	int segEndPosition;
2580	int deltaFlowPosition;
2581	int deltaSegPosition;
2582	int deltaSegHint;
2583	int flowPosition;
2584	int segPosition;
2585
2586	if (info.flow == QListView::LeftToRight) {
2587	segStartPosition = info.bounds.left();
2588	segEndPosition = info.bounds.width();
2589	flowPosition = topLeft.x();
2590	segPosition = topLeft.y();
2591	deltaFlowPosition = info.grid.width(); // dx
2592	deltaSegPosition = useItemSize ? batchSavedDeltaSeg : info.grid.height(); // dy
2593	deltaSegHint = info.grid.height();
2594	} else { // flow == QListView::TopToBottom
2595	segStartPosition = info.bounds.top();
2596	segEndPosition = info.bounds.height();
2597	flowPosition = topLeft.y();
2598	segPosition = topLeft.x();
2599	deltaFlowPosition = info.grid.height(); // dy
2600	deltaSegPosition = useItemSize ? batchSavedDeltaSeg : info.grid.width(); // dx
2601	deltaSegHint = info.grid.width();
2602	}
2603
2604	for (int row = info.first; row <= info.last; ++row) {
2605	if (isHidden(row)) { // ###
2606	flowPositions.append(t: flowPosition);
2607	} else {
2608	// if we are not using a grid, we need to find the deltas
2609	if (useItemSize) {
2610	QSize hint = itemSize(opt: option, idx: modelIndex(row));
2611	if (info.flow == QListView::LeftToRight) {
2612	deltaFlowPosition = hint.width() + info.spacing;
2613	deltaSegHint = hint.height() + info.spacing;
2614	} else { // TopToBottom
2615	deltaFlowPosition = hint.height() + info.spacing;
2616	deltaSegHint = hint.width() + info.spacing;
2617	}
2618	}
2619	// create new segment
2620	if (info.wrap && (flowPosition + deltaFlowPosition >= segEndPosition)) {
2621	segmentExtents.append(t: flowPosition);
2622	flowPosition = info.spacing + segStartPosition;
2623	segPosition += info.spacing + deltaSegPosition;
2624	segmentPositions.append(t: segPosition);
2625	segmentStartRows.append(t: row);
2626	deltaSegPosition = 0;
2627	}
2628	// save the flow position of this item
2629	scrollValueMap.append(t: flowPositions.size());
2630	flowPositions.append(t: flowPosition);
2631	// prepare for the next item
2632	deltaSegPosition = qMax(a: deltaSegHint, b: deltaSegPosition);
2633	flowPosition += info.spacing + deltaFlowPosition;
2634	}
2635	}
2636	// used when laying out next batch
2637	batchSavedPosition = flowPosition;
2638	batchSavedDeltaSeg = deltaSegPosition;
2639	batchStartRow = info.last + 1;
2640	if (info.last == info.max)
2641	flowPosition -= info.spacing; // remove extra spacing
2642	// set the contents size
2643	QRect rect = info.bounds;
2644	if (info.flow == QListView::LeftToRight) {
2645	rect.setRight(segmentPositions.size() == 1 ? flowPosition : info.bounds.right());
2646	rect.setBottom(segPosition + deltaSegPosition);
2647	} else { // TopToBottom
2648	rect.setRight(segPosition + deltaSegPosition);
2649	rect.setBottom(segmentPositions.size() == 1 ? flowPosition : info.bounds.bottom());
2650	}
2651	contentsSize = QSize(rect.right(), rect.bottom());
2652	// if it is the last batch, save the end of the segments
2653	if (info.last == info.max) {
2654	segmentExtents.append(t: flowPosition);
2655	scrollValueMap.append(t: flowPositions.size());
2656	flowPositions.append(t: flowPosition);
2657	segmentPositions.append(t: info.wrap ? segPosition + deltaSegPosition : INT_MAX);
2658	}
2659	// if the new items are visible, update the viewport
2660	QRect changedRect(topLeft, rect.bottomRight());
2661	if (clipRect().intersects(r: changedRect))
2662	viewport()->update();
2663	}
2664
2665	/*!
2666	\internal
2667	Finds the set of items intersecting with \a area.
2668	In this function, itemsize is counted from topleft to the start of the next item.
2669	*/
2670	QList<QModelIndex> QListModeViewBase::intersectingSet(const QRect &area) const
2671	{
2672	QList<QModelIndex> ret;
2673	int segStartPosition;
2674	int segEndPosition;
2675	int flowStartPosition;
2676	int flowEndPosition;
2677	if (flow() == QListView::LeftToRight) {
2678	segStartPosition = area.top();
2679	segEndPosition = area.bottom();
2680	flowStartPosition = area.left();
2681	flowEndPosition = area.right();
2682	} else {
2683	segStartPosition = area.left();
2684	segEndPosition = area.right();
2685	flowStartPosition = area.top();
2686	flowEndPosition = area.bottom();
2687	}
2688	if (segmentPositions.size() < 2 || flowPositions.isEmpty())
2689	return ret;
2690	// the last segment position is actually the edge of the last segment
2691	const int segLast = segmentPositions.size() - 2;
2692	int seg = qBinarySearch<int>(vec: segmentPositions, item: segStartPosition, start: 0, end: segLast + 1);
2693	for (; seg <= segLast && segmentPositions.at(i: seg) <= segEndPosition; ++seg) {
2694	int first = segmentStartRows.at(i: seg);
2695	int last = (seg < segLast ? segmentStartRows.at(i: seg + 1) : batchStartRow) - 1;
2696	if (segmentExtents.at(i: seg) < flowStartPosition)
2697	continue;
2698	int row = qBinarySearch<int>(vec: flowPositions, item: flowStartPosition, start: first, end: last);
2699	for (; row <= last && flowPositions.at(i: row) <= flowEndPosition; ++row) {
2700	if (isHidden(row))
2701	continue;
2702	QModelIndex index = modelIndex(row);
2703	if (index.isValid()) {
2704	if (flow() == QListView::LeftToRight || dd->itemAlignment == Qt::Alignment()) {
2705	ret += index;
2706	} else {
2707	const auto viewItem = indexToListViewItem(index);
2708	const int iw = viewItem.width();
2709	const int startPos = qMax(a: segStartPosition, b: segmentPositions.at(i: seg));
2710	const int endPos = qMin(a: segmentPositions.at(i: seg + 1), b: segEndPosition);
2711	if (endPos >= viewItem.x && startPos < viewItem.x + iw)
2712	ret += index;
2713	}
2714	}
2715	#if 0 // for debugging
2716	else
2717	qWarning("intersectingSet: row %d was invalid", row);
2718	#endif
2719	}
2720	}
2721	return ret;
2722	}
2723
2724	void QListModeViewBase::dataChanged(const QModelIndex &, const QModelIndex &)
2725	{
2726	dd->doDelayedItemsLayout();
2727	}
2728
2729
2730	QRect QListModeViewBase::mapToViewport(const QRect &rect) const
2731	{
2732	if (isWrapping())
2733	return rect;
2734	// If the listview is in "listbox-mode", the items are as wide as the view.
2735	// But we don't shrink the items.
2736	QRect result = rect;
2737	if (flow() == QListView::TopToBottom) {
2738	result.setLeft(spacing());
2739	result.setWidth(qMax(a: rect.width(), b: qMax(a: contentsSize.width(), b: viewport()->width()) - 2 * spacing()));
2740	} else { // LeftToRight
2741	result.setTop(spacing());
2742	result.setHeight(qMax(a: rect.height(), b: qMax(a: contentsSize.height(), b: viewport()->height()) - 2 * spacing()));
2743	}
2744	return result;
2745	}
2746
2747	int QListModeViewBase::perItemScrollingPageSteps(int length, int bounds, bool wrap) const
2748	{
2749	QList<int> positions;
2750	if (wrap)
2751	positions = segmentPositions;
2752	else if (!flowPositions.isEmpty()) {
2753	positions.reserve(asize: scrollValueMap.size());
2754	for (int itemShown : scrollValueMap)
2755	positions.append(t: flowPositions.at(i: itemShown));
2756	}
2757	if (positions.isEmpty() || bounds <= length)
2758	return positions.size();
2759	if (uniformItemSizes()) {
2760	for (int i = 1; i < positions.size(); ++i)
2761	if (positions.at(i) > 0)
2762	return length / positions.at(i);
2763	return 0; // all items had height 0
2764	}
2765	int pageSteps = 0;
2766	int steps = positions.size() - 1;
2767	int max = qMax(a: length, b: bounds);
2768	int min = qMin(a: length, b: bounds);
2769	int pos = min - (max - positions.constLast());
2770
2771	while (pos >= 0 && steps > 0) {
2772	pos -= (positions.at(i: steps) - positions.at(i: steps - 1));
2773	if (pos >= 0) //this item should be visible
2774	++pageSteps;
2775	--steps;
2776	}
2777
2778	// at this point we know that positions has at least one entry
2779	return qMax(a: pageSteps, b: 1);
2780	}
2781
2782	int QListModeViewBase::perItemScrollToValue(int index, int scrollValue, int viewportSize,
2783	QAbstractItemView::ScrollHint hint,
2784	Qt::Orientation orientation, bool wrap, int itemExtent) const
2785	{
2786	if (index < 0)
2787	return scrollValue;
2788
2789	itemExtent += spacing();
2790	QList<int> hiddenRows = dd->hiddenRowIds();
2791	std::sort(first: hiddenRows.begin(), last: hiddenRows.end());
2792	int hiddenRowsBefore = 0;
2793	for (int i = 0; i < hiddenRows.size() - 1; ++i)
2794	if (hiddenRows.at(i) > index + hiddenRowsBefore)
2795	break;
2796	else
2797	++hiddenRowsBefore;
2798	if (!wrap) {
2799	int topIndex = index;
2800	const int bottomIndex = topIndex;
2801	const int bottomCoordinate = flowPositions.at(i: index + hiddenRowsBefore);
2802	while (topIndex > 0 &&
2803	(bottomCoordinate - flowPositions.at(i: topIndex + hiddenRowsBefore - 1) + itemExtent) <= (viewportSize)) {
2804	topIndex--;
2805	// will the next one be a hidden row -> skip
2806	while (hiddenRowsBefore > 0 && hiddenRows.at(i: hiddenRowsBefore - 1) >= topIndex + hiddenRowsBefore - 1)
2807	hiddenRowsBefore--;
2808	}
2809
2810	const int itemCount = bottomIndex - topIndex + 1;
2811	switch (hint) {
2812	case QAbstractItemView::PositionAtTop:
2813	return index;
2814	case QAbstractItemView::PositionAtBottom:
2815	return index - itemCount + 1;
2816	case QAbstractItemView::PositionAtCenter:
2817	return index - (itemCount / 2);
2818	default:
2819	break;
2820	}
2821	} else { // wrapping
2822	Qt::Orientation flowOrientation = (flow() == QListView::LeftToRight
2823	? Qt::Horizontal : Qt::Vertical);
2824	if (flowOrientation == orientation) { // scrolling in the "flow" direction
2825	// ### wrapped scrolling in the flow direction
2826	return flowPositions.at(i: index + hiddenRowsBefore); // ### always pixel based for now
2827	} else if (!segmentStartRows.isEmpty()) { // we are scrolling in the "segment" direction
2828	int segment = qBinarySearch<int>(vec: segmentStartRows, item: index, start: 0, end: segmentStartRows.size() - 1);
2829	int leftSegment = segment;
2830	const int rightSegment = leftSegment;
2831	const int bottomCoordinate = segmentPositions.at(i: segment);
2832
2833	while (leftSegment > scrollValue &&
2834	(bottomCoordinate - segmentPositions.at(i: leftSegment-1) + itemExtent) <= (viewportSize)) {
2835	leftSegment--;
2836	}
2837
2838	const int segmentCount = rightSegment - leftSegment + 1;
2839	switch (hint) {
2840	case QAbstractItemView::PositionAtTop:
2841	return segment;
2842	case QAbstractItemView::PositionAtBottom:
2843	return segment - segmentCount + 1;
2844	case QAbstractItemView::PositionAtCenter:
2845	return segment - (segmentCount / 2);
2846	default:
2847	break;
2848	}
2849	}
2850	}
2851	return scrollValue;
2852	}
2853
2854	void QListModeViewBase::clear()
2855	{
2856	flowPositions.clear();
2857	segmentPositions.clear();
2858	segmentStartRows.clear();
2859	segmentExtents.clear();
2860	batchSavedPosition = 0;
2861	batchStartRow = 0;
2862	batchSavedDeltaSeg = 0;
2863	}
2864
2865	/*
2866	* IconMode ListView Implementation
2867	*/
2868
2869	void QIconModeViewBase::setPositionForIndex(const QPoint &position, const QModelIndex &index)
2870	{
2871	if (index.row() >= items.size())
2872	return;
2873	const QSize oldContents = contentsSize;
2874	qq->update(index); // update old position
2875	moveItem(index: index.row(), dest: position);
2876	qq->update(index); // update new position
2877
2878	if (contentsSize != oldContents)
2879	dd->viewUpdateGeometries(); // update the scroll bars
2880	}
2881
2882	void QIconModeViewBase::appendHiddenRow(int row)
2883	{
2884	if (row >= 0 && row < items.size()) //remove item
2885	tree.removeLeaf(r: items.at(i: row).rect(), i: row);
2886	QCommonListViewBase::appendHiddenRow(row);
2887	}
2888
2889	void QIconModeViewBase::removeHiddenRow(int row)
2890	{
2891	QCommonListViewBase::removeHiddenRow(row);
2892	if (row >= 0 && row < items.size()) //insert item
2893	tree.insertLeaf(r: items.at(i: row).rect(), i: row);
2894	}
2895
2896	#if QT_CONFIG(draganddrop)
2897	bool QIconModeViewBase::filterStartDrag(Qt::DropActions supportedActions)
2898	{
2899	// This function does the same thing as in QAbstractItemView::startDrag(),
2900	// plus adding viewitems to the draggedItems list.
2901	// We need these items to draw the drag items
2902	QModelIndexList indexes = dd->selectionModel->selectedIndexes();
2903	if (indexes.size() > 0 ) {
2904	if (viewport()->acceptDrops()) {
2905	QModelIndexList::ConstIterator it = indexes.constBegin();
2906	for (; it != indexes.constEnd(); ++it)
2907	if (dd->model->flags(index: *it) & Qt::ItemIsDragEnabled
2908	&& (*it).column() == dd->column)
2909	draggedItems.push_back(t: *it);
2910	}
2911
2912	QRect rect;
2913	QPixmap pixmap = dd->renderToPixmap(indexes, r: &rect);
2914	rect.adjust(dx1: horizontalOffset(), dy1: verticalOffset(), dx2: 0, dy2: 0);
2915	QDrag *drag = new QDrag(qq);
2916	drag->setMimeData(dd->model->mimeData(indexes));
2917	drag->setPixmap(pixmap);
2918	drag->setHotSpot(dd->pressedPosition - rect.topLeft());
2919	dd->dropEventMoved = false;
2920	Qt::DropAction action = drag->exec(supportedActions, defaultAction: dd->defaultDropAction);
2921	draggedItems.clear();
2922	// delete item, unless it has already been moved internally (see filterDropEvent)
2923	if (action == Qt::MoveAction && !dd->dropEventMoved) {
2924	if (dd->dragDropMode != QAbstractItemView::InternalMove || drag->target() == qq->viewport())
2925	dd->clearOrRemove();
2926	}
2927	dd->dropEventMoved = false;
2928	}
2929	return true;
2930	}
2931
2932	bool QIconModeViewBase::filterDropEvent(QDropEvent *e)
2933	{
2934	if (e->source() != qq)
2935	return false;
2936
2937	const QSize contents = contentsSize;
2938	QPoint offset(horizontalOffset(), verticalOffset());
2939	QPoint end = e->position().toPoint() + offset;
2940	if (qq->acceptDrops()) {
2941	const Qt::ItemFlags dropableFlags = Qt::ItemIsDropEnabled|Qt::ItemIsEnabled;
2942	const QList<QModelIndex> &dropIndices = intersectingSet(area: QRect(end, QSize(1, 1)));
2943	for (const QModelIndex &index : dropIndices)
2944	if ((index.flags() & dropableFlags) == dropableFlags)
2945	return false;
2946	}
2947	QPoint start = dd->pressedPosition;
2948	QPoint delta = (dd->movement == QListView::Snap ? snapToGrid(pos: end) - snapToGrid(pos: start) : end - start);
2949	const QList<QModelIndex> indexes = dd->selectionModel->selectedIndexes();
2950	for (const auto &index : indexes) {
2951	QRect rect = dd->rectForIndex(index);
2952	viewport()->update(dd->mapToViewport(rect, extend: false));
2953	QPoint dest = rect.topLeft() + delta;
2954	if (qq->isRightToLeft())
2955	dest.setX(dd->flipX(x: dest.x()) - rect.width());
2956	moveItem(index: index.row(), dest);
2957	qq->update(index);
2958	}
2959	dd->stopAutoScroll();
2960	draggedItems.clear();
2961	dd->emitIndexesMoved(indexes);
2962	// do not delete item on internal move, see filterStartDrag()
2963	dd->dropEventMoved = true;
2964	e->accept(); // we have handled the event
2965	// if the size has not grown, we need to check if it has shrunk
2966	if (contentsSize != contents) {
2967	if ((contentsSize.width() <= contents.width()
2968	|| contentsSize.height() <= contents.height())) {
2969	updateContentsSize();
2970	}
2971	dd->viewUpdateGeometries();
2972	}
2973	return true;
2974	}
2975
2976	bool QIconModeViewBase::filterDragLeaveEvent(QDragLeaveEvent *e)
2977	{
2978	viewport()->update(draggedItemsRect()); // erase the area
2979	draggedItemsPos = QPoint(-1, -1); // don't draw the dragged items
2980	return QCommonListViewBase::filterDragLeaveEvent(e);
2981	}
2982
2983	bool QIconModeViewBase::filterDragMoveEvent(QDragMoveEvent *e)
2984	{
2985	const bool wasAccepted = e->isAccepted();
2986
2987	// ignore by default
2988	e->ignore();
2989
2990	if (e->source() != qq || !dd->canDrop(event: e)) {
2991	// restore previous acceptance on failure
2992	e->setAccepted(wasAccepted);
2993	return false;
2994	}
2995
2996	// get old dragged items rect
2997	QRect itemsRect = this->itemsRect(indexes: draggedItems);
2998	viewport()->update(itemsRect.translated(p: draggedItemsDelta()));
2999	// update position
3000	draggedItemsPos = e->position().toPoint();
3001	// get new items rect
3002	viewport()->update(itemsRect.translated(p: draggedItemsDelta()));
3003	// set the item under the cursor to current
3004	QModelIndex index;
3005	if (movement() == QListView::Snap) {
3006	QRect rect(snapToGrid(pos: e->position().toPoint() + offset()), gridSize());
3007	const QList<QModelIndex> intersectVector = intersectingSet(area: rect);
3008	index = intersectVector.size() > 0 ? intersectVector.last() : QModelIndex();
3009	} else {
3010	index = qq->indexAt(p: e->position().toPoint());
3011	}
3012	// check if we allow drops here
3013	if (draggedItems.contains(t: index))
3014	e->accept(); // allow changing item position
3015	else if (dd->model->flags(index) & Qt::ItemIsDropEnabled)
3016	e->accept(); // allow dropping on dropenabled items
3017	else if (!index.isValid())
3018	e->accept(); // allow dropping in empty areas
3019
3020	// the event was treated. do autoscrolling
3021	if (dd->shouldAutoScroll(pos: e->position().toPoint()))
3022	dd->startAutoScroll();
3023	return true;
3024	}
3025	#endif // QT_CONFIG(draganddrop)
3026
3027	void QIconModeViewBase::setRowCount(int rowCount)
3028	{
3029	tree.create(n: qMax(a: rowCount - hiddenCount(), b: 0));
3030	}
3031
3032	void QIconModeViewBase::scrollContentsBy(int dx, int dy, bool scrollElasticBand)
3033	{
3034	if (scrollElasticBand)
3035	dd->scrollElasticBandBy(dx: isRightToLeft() ? -dx : dx, dy);
3036
3037	QCommonListViewBase::scrollContentsBy(dx, dy, scrollElasticBand);
3038	if (!draggedItems.isEmpty())
3039	viewport()->update(draggedItemsRect().translated(dx, dy));
3040	}
3041
3042	void QIconModeViewBase::dataChanged(const QModelIndex &topLeft, const QModelIndex &bottomRight)
3043	{
3044	if (column() >= topLeft.column() && column() <= bottomRight.column()) {
3045	QStyleOptionViewItem option;
3046	initViewItemOption(option: &option);
3047	const int bottom = qMin(a: items.size(), b: bottomRight.row() + 1);
3048	const bool useItemSize = !dd->grid.isValid();
3049	for (int row = topLeft.row(); row < bottom; ++row)
3050	{
3051	QSize s = itemSize(opt: option, idx: modelIndex(row));
3052	if (!useItemSize)
3053	{
3054	s.setWidth(qMin(a: dd->grid.width(), b: s.width()));
3055	s.setHeight(qMin(a: dd->grid.height(), b: s.height()));
3056	}
3057	items[row].resize(size: s);
3058	}
3059	}
3060	}
3061
3062	bool QIconModeViewBase::doBatchedItemLayout(const QListViewLayoutInfo &info, int max)
3063	{
3064	if (info.last >= items.size()) {
3065	//first we create the items
3066	QStyleOptionViewItem option;
3067	initViewItemOption(option: &option);
3068	for (int row = items.size(); row <= info.last; ++row) {
3069	QSize size = itemSize(opt: option, idx: modelIndex(row));
3070	QListViewItem item(QRect(0, 0, size.width(), size.height()), row); // default pos
3071	items.append(t: item);
3072	}
3073	doDynamicLayout(info);
3074	}
3075	return (batchStartRow > max); // done
3076	}
3077
3078	QListViewItem QIconModeViewBase::indexToListViewItem(const QModelIndex &index) const
3079	{
3080	if (index.isValid() && index.row() < items.size())
3081	return items.at(i: index.row());
3082	return QListViewItem();
3083	}
3084
3085	void QIconModeViewBase::initBspTree(const QSize &contents)
3086	{
3087	// remove all items from the tree
3088	int leafCount = tree.leafCount();
3089	for (int l = 0; l < leafCount; ++l)
3090	tree.leaf(i: l).clear();
3091	// we have to get the bounding rect of the items before we can initialize the tree
3092	QBspTree::Node::Type type = QBspTree::Node::Both; // 2D
3093	// simple heuristics to get better bsp
3094	if (contents.height() / contents.width() >= 3)
3095	type = QBspTree::Node::HorizontalPlane;
3096	else if (contents.width() / contents.height() >= 3)
3097	type = QBspTree::Node::VerticalPlane;
3098	// build tree for the bounding rect (not just the contents rect)
3099	tree.init(area: QRect(0, 0, contents.width(), contents.height()), type);
3100	}
3101
3102	QPoint QIconModeViewBase::initDynamicLayout(const QListViewLayoutInfo &info)
3103	{
3104	int x, y;
3105	if (info.first == 0) {
3106	x = info.bounds.x() + info.spacing;
3107	y = info.bounds.y() + info.spacing;
3108	items.reserve(asize: rowCount() - hiddenCount());
3109	} else {
3110	int idx = info.first - 1;
3111	while (idx > 0 && !items.at(i: idx).isValid())
3112	--idx;
3113	const QListViewItem &item = items.at(i: idx);
3114	x = item.x;
3115	y = item.y;
3116	if (info.flow == QListView::LeftToRight)
3117	x += (info.grid.isValid() ? info.grid.width() : item.w) + info.spacing;
3118	else
3119	y += (info.grid.isValid() ? info.grid.height() : item.h) + info.spacing;
3120	}
3121	return QPoint(x, y);
3122	}
3123
3124	/*!
3125	\internal
3126	*/
3127	void QIconModeViewBase::doDynamicLayout(const QListViewLayoutInfo &info)
3128	{
3129	const bool useItemSize = !info.grid.isValid();
3130	const QPoint topLeft = initDynamicLayout(info);
3131
3132	int segStartPosition;
3133	int segEndPosition;
3134	int deltaFlowPosition;
3135	int deltaSegPosition;
3136	int deltaSegHint;
3137	int flowPosition;
3138	int segPosition;
3139
3140	if (info.flow == QListView::LeftToRight) {
3141	segStartPosition = info.bounds.left() + info.spacing;
3142	segEndPosition = info.bounds.right();
3143	deltaFlowPosition = info.grid.width(); // dx
3144	deltaSegPosition = (useItemSize ? batchSavedDeltaSeg : info.grid.height()); // dy
3145	deltaSegHint = info.grid.height();
3146	flowPosition = topLeft.x();
3147	segPosition = topLeft.y();
3148	} else { // flow == QListView::TopToBottom
3149	segStartPosition = info.bounds.top() + info.spacing;
3150	segEndPosition = info.bounds.bottom();
3151	deltaFlowPosition = info.grid.height(); // dy
3152	deltaSegPosition = (useItemSize ? batchSavedDeltaSeg : info.grid.width()); // dx
3153	deltaSegHint = info.grid.width();
3154	flowPosition = topLeft.y();
3155	segPosition = topLeft.x();
3156	}
3157
3158	if (moved.size() != items.size())
3159	moved.resize(size: items.size());
3160
3161	QRect rect(QPoint(), topLeft);
3162	QListViewItem *item = nullptr;
3163	Q_ASSERT(info.first <= info.last);
3164	for (int row = info.first; row <= info.last; ++row) {
3165	item = &items[row];
3166	if (isHidden(row)) {
3167	item->invalidate();
3168	} else {
3169	// if we are not using a grid, we need to find the deltas
3170	if (useItemSize) {
3171	if (info.flow == QListView::LeftToRight)
3172	deltaFlowPosition = item->w + info.spacing;
3173	else
3174	deltaFlowPosition = item->h + info.spacing;
3175	} else {
3176	item->w = qMin<int>(a: info.grid.width(), b: item->w);
3177	item->h = qMin<int>(a: info.grid.height(), b: item->h);
3178	}
3179
3180	// create new segment
3181	if (info.wrap
3182	&& flowPosition + deltaFlowPosition > segEndPosition
3183	&& flowPosition > segStartPosition) {
3184	flowPosition = segStartPosition;
3185	segPosition += deltaSegPosition;
3186	if (useItemSize)
3187	deltaSegPosition = 0;
3188	}
3189	// We must delay calculation of the seg adjustment, as this item
3190	// may have caused a wrap to occur
3191	if (useItemSize) {
3192	if (info.flow == QListView::LeftToRight)
3193	deltaSegHint = item->h + info.spacing;
3194	else
3195	deltaSegHint = item->w + info.spacing;
3196	deltaSegPosition = qMax(a: deltaSegPosition, b: deltaSegHint);
3197	}
3198
3199	// set the position of the item
3200	// ### idealy we should have some sort of alignment hint for the item
3201	// ### (normally that would be a point between the icon and the text)
3202	if (!moved.testBit(i: row)) {
3203	if (info.flow == QListView::LeftToRight) {
3204	if (useItemSize) {
3205	item->x = flowPosition;
3206	item->y = segPosition;
3207	} else { // use grid
3208	item->x = flowPosition + ((deltaFlowPosition - item->w) / 2);
3209	item->y = segPosition;
3210	}
3211	} else { // TopToBottom
3212	if (useItemSize) {
3213	item->y = flowPosition;
3214	item->x = segPosition;
3215	} else { // use grid
3216	item->y = flowPosition + ((deltaFlowPosition - item->h) / 2);
3217	item->x = segPosition;
3218	}
3219	}
3220	}
3221
3222	// let the contents contain the new item
3223	if (useItemSize)
3224	rect |= item->rect();
3225	else if (info.flow == QListView::LeftToRight)
3226	rect |= QRect(flowPosition, segPosition, deltaFlowPosition, deltaSegPosition);
3227	else // flow == TopToBottom
3228	rect |= QRect(segPosition, flowPosition, deltaSegPosition, deltaFlowPosition);
3229
3230	// prepare for next item
3231	flowPosition += deltaFlowPosition; // current position + item width + gap
3232	}
3233	}
3234	Q_ASSERT(item);
3235	batchSavedDeltaSeg = deltaSegPosition;
3236	batchStartRow = info.last + 1;
3237	bool done = (info.last >= rowCount() - 1);
3238	// resize the content area
3239	if (done || !info.bounds.contains(r: item->rect())) {
3240	contentsSize = rect.size();
3241	if (info.flow == QListView::LeftToRight)
3242	contentsSize.rheight() += info.spacing;
3243	else
3244	contentsSize.rwidth() += info.spacing;
3245	}
3246	if (rect.size().isEmpty())
3247	return;
3248	// resize tree
3249	int insertFrom = info.first;
3250	if (done || info.first == 0) {
3251	initBspTree(contents: rect.size());
3252	insertFrom = 0;
3253	}
3254	// insert items in tree
3255	for (int row = insertFrom; row <= info.last; ++row)
3256	tree.insertLeaf(r: items.at(i: row).rect(), i: row);
3257	// if the new items are visible, update the viewport
3258	QRect changedRect(topLeft, rect.bottomRight());
3259	if (clipRect().intersects(r: changedRect))
3260	viewport()->update();
3261	}
3262
3263	QList<QModelIndex> QIconModeViewBase::intersectingSet(const QRect &area) const
3264	{
3265	QIconModeViewBase *that = const_cast<QIconModeViewBase*>(this);
3266	QBspTree::Data data(static_cast<void*>(that));
3267	QList<QModelIndex> res;
3268	that->interSectingVector = &res;
3269	that->tree.climbTree(rect: area, function: &QIconModeViewBase::addLeaf, data);
3270	that->interSectingVector = nullptr;
3271	return res;
3272	}
3273
3274	QRect QIconModeViewBase::itemsRect(const QList<QModelIndex> &indexes) const
3275	{
3276	QRect rect;
3277	for (const auto &index : indexes)
3278	rect |= viewItemRect(item: indexToListViewItem(index));
3279	return rect;
3280	}
3281
3282	int QIconModeViewBase::itemIndex(const QListViewItem &item) const
3283	{
3284	if (!item.isValid())
3285	return -1;
3286	int i = item.indexHint;
3287	if (i < items.size()) {
3288	if (items.at(i) == item)
3289	return i;
3290	} else {
3291	i = items.size() - 1;
3292	}
3293
3294	int j = i;
3295	int c = items.size();
3296	bool a = true;
3297	bool b = true;
3298
3299	while (a || b) {
3300	if (a) {
3301	if (items.at(i) == item) {
3302	items.at(i).indexHint = i;
3303	return i;
3304	}
3305	a = ++i < c;
3306	}
3307	if (b) {
3308	if (items.at(i: j) == item) {
3309	items.at(i: j).indexHint = j;
3310	return j;
3311	}
3312	b = --j > -1;
3313	}
3314	}
3315	return -1;
3316	}
3317
3318	void QIconModeViewBase::addLeaf(QList<int> &leaf, const QRect &area, uint visited,
3319	QBspTree::Data data)
3320	{
3321	QListViewItem *vi;
3322	QIconModeViewBase *_this = static_cast<QIconModeViewBase *>(data.ptr);
3323	for (int i = 0; i < leaf.size(); ++i) {
3324	int idx = leaf.at(i);
3325	if (idx < 0 || idx >= _this->items.size())
3326	continue;
3327	vi = &_this->items[idx];
3328	Q_ASSERT(vi);
3329	if (vi->isValid() && vi->rect().intersects(r: area) && vi->visited != visited) {
3330	QModelIndex index = _this->dd->listViewItemToIndex(item: *vi);
3331	Q_ASSERT(index.isValid());
3332	_this->interSectingVector->append(t: index);
3333	vi->visited = visited;
3334	}
3335	}
3336	}
3337
3338	void QIconModeViewBase::moveItem(int index, const QPoint &dest)
3339	{
3340	// does not impact on the bintree itself or the contents rect
3341	QListViewItem *item = &items[index];
3342	QRect rect = item->rect();
3343
3344	// move the item without removing it from the tree
3345	tree.removeLeaf(r: rect, i: index);
3346	item->move(position: dest);
3347	tree.insertLeaf(r: QRect(dest, rect.size()), i: index);
3348
3349	// resize the contents area
3350	contentsSize = (QRect(QPoint(0, 0), contentsSize)|QRect(dest, rect.size())).size();
3351
3352	// mark the item as moved
3353	if (moved.size() != items.size())
3354	moved.resize(size: items.size());
3355	moved.setBit(i: index, val: true);
3356	}
3357
3358	QPoint QIconModeViewBase::snapToGrid(const QPoint &pos) const
3359	{
3360	int x = pos.x() - (pos.x() % gridSize().width());
3361	int y = pos.y() - (pos.y() % gridSize().height());
3362	return QPoint(x, y);
3363	}
3364
3365	QPoint QIconModeViewBase::draggedItemsDelta() const
3366	{
3367	if (movement() == QListView::Snap) {
3368	QPoint snapdelta = QPoint((offset().x() % gridSize().width()),
3369	(offset().y() % gridSize().height()));
3370	return snapToGrid(pos: draggedItemsPos + snapdelta) - snapToGrid(pos: pressedPosition()) - snapdelta;
3371	}
3372	return draggedItemsPos - pressedPosition();
3373	}
3374
3375	QRect QIconModeViewBase::draggedItemsRect() const
3376	{
3377	QRect rect = itemsRect(indexes: draggedItems);
3378	rect.translate(p: draggedItemsDelta());
3379	return rect;
3380	}
3381
3382	void QListViewPrivate::scrollElasticBandBy(int dx, int dy)
3383	{
3384	if (dx > 0) // right
3385	elasticBand.moveRight(pos: elasticBand.right() + dx);
3386	else if (dx < 0) // left
3387	elasticBand.moveLeft(pos: elasticBand.left() - dx);
3388	if (dy > 0) // down
3389	elasticBand.moveBottom(pos: elasticBand.bottom() + dy);
3390	else if (dy < 0) // up
3391	elasticBand.moveTop(pos: elasticBand.top() - dy);
3392	}
3393
3394	void QIconModeViewBase::clear()
3395	{
3396	tree.destroy();
3397	items.clear();
3398	moved.clear();
3399	batchStartRow = 0;
3400	batchSavedDeltaSeg = 0;
3401	}
3402
3403	void QIconModeViewBase::updateContentsSize()
3404	{
3405	QRect bounding;
3406	for (int i = 0; i < items.size(); ++i)
3407	bounding |= items.at(i).rect();
3408	contentsSize = bounding.size();
3409	}
3410
3411	/*!
3412	\reimp
3413	*/
3414	void QListView::currentChanged(const QModelIndex &current, const QModelIndex &previous)
3415	{
3416	QAbstractItemView::currentChanged(current, previous);
3417	#if QT_CONFIG(accessibility)
3418	if (QAccessible::isActive()) {
3419	if (current.isValid() && hasFocus()) {
3420	int entry = visualIndex(index: current);
3421	QAccessibleEvent event(this, QAccessible::Focus);
3422	event.setChild(entry);
3423	QAccessible::updateAccessibility(event: &event);
3424	}
3425	}
3426	#endif
3427	}
3428
3429	/*!
3430	\reimp
3431	*/
3432	void QListView::selectionChanged(const QItemSelection &selected,
3433	const QItemSelection &deselected)
3434	{
3435	#if QT_CONFIG(accessibility)
3436	if (QAccessible::isActive()) {
3437	// ### does not work properly for selection ranges.
3438	QModelIndex sel = selected.indexes().value(i: 0);
3439	if (sel.isValid()) {
3440	int entry = visualIndex(index: sel);
3441	QAccessibleEvent event(this, QAccessible::SelectionAdd);
3442	event.setChild(entry);
3443	QAccessible::updateAccessibility(event: &event);
3444	}
3445	QModelIndex desel = deselected.indexes().value(i: 0);
3446	if (desel.isValid()) {
3447	int entry = visualIndex(index: desel);
3448	QAccessibleEvent event(this, QAccessible::SelectionRemove);
3449	event.setChild(entry);
3450	QAccessible::updateAccessibility(event: &event);
3451	}
3452	}
3453	#endif
3454	QAbstractItemView::selectionChanged(selected, deselected);
3455	}
3456
3457	int QListView::visualIndex(const QModelIndex &index) const
3458	{
3459	Q_D(const QListView);
3460	d->executePostedLayout();
3461	QListViewItem itm = d->indexToListViewItem(index);
3462	int visualIndex = d->commonListView->itemIndex(item: itm);
3463	for (const auto &idx : std::as_const(t: d->hiddenRows)) {
3464	if (idx.row() <= index.row())
3465	--visualIndex;
3466	}
3467	return visualIndex;
3468	}
3469
3470
3471	/*!
3472	\since 5.2
3473	\reimp
3474	*/
3475	QSize QListView::viewportSizeHint() const
3476	{
3477	Q_D(const QListView);
3478	// We don't have a nice simple size hint for invalid or wrapping list views.
3479	if (!d->model)
3480	return QAbstractItemView::viewportSizeHint();
3481	const int rc = d->model->rowCount();
3482	if (rc == 0 || isWrapping())
3483	return QAbstractItemView::viewportSizeHint();
3484
3485	QStyleOptionViewItem option;
3486	initViewItemOption(option: &option);
3487
3488	if (uniformItemSizes()) {
3489	QSize sz = d->cachedItemSize;
3490	if (!sz.isValid()) {
3491	QModelIndex idx = d->model->index(row: 0, column: d->column, parent: d->root);
3492	sz = d->itemSize(option, index: idx);
3493	}
3494	sz.setHeight(rc * sz.height());
3495	return sz;
3496	}
3497
3498	// Using AdjustToContents with a high number of rows will normally not make sense, so we limit
3499	// this to default 1000 (that is btw the default for QHeaderView::resizeContentsPrecision())
3500	// (By setting the property _q_resizeContentPrecision the user can however override this).
3501	int maximumRows = 1000;
3502	const QVariant userOverrideValue = property(name: "_q_resizeContentPrecision");
3503	if (userOverrideValue.isValid() && userOverrideValue.toInt() > 0) {
3504	maximumRows = userOverrideValue.toInt();
3505	}
3506	const int rowCount = qMin(a: rc, b: maximumRows);
3507
3508	int h = 0;
3509	int w = 0;
3510
3511	for (int row = 0; row < rowCount; ++row) {
3512	QModelIndex idx = d->model->index(row, column: d->column, parent: d->root);
3513	QSize itemSize = d->itemSize(option, index: idx);
3514	h += itemSize.height();
3515	w = qMax(a: w, b: itemSize.width());
3516	}
3517	return QSize(w, h);
3518	}
3519
3520	QT_END_NAMESPACE
3521
3522	#include "moc_qlistview.cpp"
3523