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39
40#include "qglobal.h"
41
42#include "qgraphicslayout_p.h"
43#include "qgraphicslayout.h"
44#include "qgraphicswidget.h"
45#include "qapplication.h"
46
47QT_BEGIN_NAMESPACE
48
49/*!
50 \internal
51
52 \a mw is the new parent. all items in the layout will be a child of \a mw.
53 */
54void QGraphicsLayoutPrivate::reparentChildItems(QGraphicsItem *newParent)
55{
56 Q_Q(QGraphicsLayout);
57 int n = q->count();
58 //bool mwVisible = mw && mw->isVisible();
59 for (int i = 0; i < n; ++i) {
60 QGraphicsLayoutItem *layoutChild = q->itemAt(i);
61 if (!layoutChild) {
62 // Skip stretch items
63 continue;
64 }
65 if (layoutChild->isLayout()) {
66 QGraphicsLayout *l = static_cast<QGraphicsLayout*>(layoutChild);
67 l->d_func()->reparentChildItems(newParent);
68 } else if (QGraphicsItem *itemChild = layoutChild->graphicsItem()){
69 QGraphicsItem *childParent = itemChild->parentItem();
70#ifdef QT_DEBUG
71 if (childParent && childParent != newParent && itemChild->isWidget() && qt_graphicsLayoutDebug()) {
72 QGraphicsWidget *w = static_cast<QGraphicsWidget*>(layoutChild);
73 qWarning(msg: "QGraphicsLayout::addChildLayout: widget %s \"%s\" in wrong parent; moved to correct parent",
74 w->metaObject()->className(), w->objectName().toLocal8Bit().constData());
75 }
76#endif
77 if (childParent != newParent)
78 itemChild->setParentItem(newParent);
79 }
80 }
81}
82
83void QGraphicsLayoutPrivate::getMargin(qreal *result, qreal userMargin, QStyle::PixelMetric pm) const
84{
85 if (!result)
86 return;
87 Q_Q(const QGraphicsLayout);
88
89 QGraphicsLayoutItem *parent = q->parentLayoutItem();
90 if (userMargin >= 0.0) {
91 *result = userMargin;
92 } else if (!parent) {
93 *result = 0.0;
94 } else if (parent->isLayout()) { // sublayouts have 0 margin by default
95 *result = 0.0;
96 } else {
97 *result = 0.0;
98 if (QGraphicsItem *layoutParentItem = parentItem()) {
99 if (layoutParentItem->isWidget())
100 *result = (qreal)static_cast<QGraphicsWidget*>(layoutParentItem)->style()->pixelMetric(metric: pm, option: nullptr);
101 }
102 }
103}
104
105Qt::LayoutDirection QGraphicsLayoutPrivate::visualDirection() const
106{
107 if (QGraphicsItem *maybeWidget = parentItem()) {
108 if (maybeWidget->isWidget())
109 return static_cast<QGraphicsWidget*>(maybeWidget)->layoutDirection();
110 }
111 return QGuiApplication::layoutDirection();
112}
113
114static bool removeLayoutItemFromLayout(QGraphicsLayout *lay, QGraphicsLayoutItem *layoutItem)
115{
116 if (!lay)
117 return false;
118
119 for (int i = lay->count() - 1; i >= 0; --i) {
120 QGraphicsLayoutItem *child = lay->itemAt(i);
121 if (child && child->isLayout()) {
122 if (removeLayoutItemFromLayout(lay: static_cast<QGraphicsLayout*>(child), layoutItem))
123 return true;
124 } else if (child == layoutItem) {
125 lay->removeAt(index: i);
126 return true;
127 }
128 }
129 return false;
130}
131
132/*!
133 \internal
134
135 This function is called from subclasses to add a layout item \a layoutItem
136 to a layout.
137
138 It takes care of automatically reparenting graphics items, if needed.
139
140 If \a layoutItem is a is already in a layout, it will remove it from that layout.
141
142*/
143void QGraphicsLayoutPrivate::addChildLayoutItem(QGraphicsLayoutItem *layoutItem)
144{
145 Q_Q(QGraphicsLayout);
146 if (QGraphicsLayoutItem *maybeLayout = layoutItem->parentLayoutItem()) {
147 if (maybeLayout->isLayout())
148 removeLayoutItemFromLayout(lay: static_cast<QGraphicsLayout*>(maybeLayout), layoutItem);
149 }
150 layoutItem->setParentLayoutItem(q);
151 if (layoutItem->isLayout()) {
152 if (QGraphicsItem *parItem = parentItem()) {
153 static_cast<QGraphicsLayout*>(layoutItem)->d_func()->reparentChildItems(newParent: parItem);
154 }
155 } else {
156 if (QGraphicsItem *item = layoutItem->graphicsItem()) {
157 QGraphicsItem *newParent = parentItem();
158 QGraphicsItem *oldParent = item->parentItem();
159 if (oldParent == newParent || !newParent)
160 return;
161
162#ifdef QT_DEBUG
163 if (oldParent && item->isWidget()) {
164 QGraphicsWidget *w = static_cast<QGraphicsWidget*>(item);
165 qWarning(msg: "QGraphicsLayout::addChildLayoutItem: %s \"%s\" in wrong parent; moved to correct parent",
166 w->metaObject()->className(), w->objectName().toLocal8Bit().constData());
167 }
168#endif
169
170 item->setParentItem(newParent);
171 }
172 }
173}
174
175void QGraphicsLayoutPrivate::activateRecursive(QGraphicsLayoutItem *item)
176{
177 if (item->isLayout()) {
178 QGraphicsLayout *layout = static_cast<QGraphicsLayout *>(item);
179 if (layout->d_func()->activated) {
180 if (QGraphicsLayout::instantInvalidatePropagation()) {
181 return;
182 } else {
183 layout->invalidate(); // ### LOOKS SUSPICIOUSLY WRONG!!???
184 }
185 }
186
187 for (int i = layout->count() - 1; i >= 0; --i) {
188 QGraphicsLayoutItem *childItem = layout->itemAt(i);
189 if (childItem)
190 activateRecursive(item: childItem);
191 }
192 layout->d_func()->activated = true;
193 }
194}
195
196QT_END_NAMESPACE
197

source code of qtbase/src/widgets/graphicsview/qgraphicslayout_p.cpp