1// Copyright (C) 2020 The Qt Company Ltd.
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4#ifndef QQUICKITEM_H
5#define QQUICKITEM_H
6
7#include <QtQuick/qtquickglobal.h>
8#include <QtQml/qqml.h>
9#include <QtQml/qqmlcomponent.h>
10
11#include <QtCore/QObject>
12#include <QtCore/QList>
13#include <QtCore/qproperty.h>
14#include <QtGui/qevent.h>
15#include <QtGui/qfont.h>
16#include <QtGui/qaccessible.h>
17
18QT_BEGIN_NAMESPACE
19
20class QQuickItem;
21class QQuickTransformPrivate;
22class Q_QUICK_EXPORT QQuickTransform : public QObject
23{
24 Q_OBJECT
25 QML_ANONYMOUS
26 QML_ADDED_IN_VERSION(2, 0)
27public:
28 explicit QQuickTransform(QObject *parent = nullptr);
29 ~QQuickTransform() override;
30
31 void appendToItem(QQuickItem *);
32 void prependToItem(QQuickItem *);
33
34 virtual void applyTo(QMatrix4x4 *matrix) const = 0;
35
36protected Q_SLOTS:
37 void update();
38
39protected:
40 QQuickTransform(QQuickTransformPrivate &dd, QObject *parent);
41
42private:
43 Q_DECLARE_PRIVATE(QQuickTransform)
44};
45
46class QCursor;
47class QQuickItemLayer;
48class QQuickState;
49class QQuickAnchorLine;
50class QQuickTransition;
51class QQuickKeyEvent;
52class QQuickAnchors;
53class QQuickItemPrivate;
54class QQuickWindow;
55class QTouchEvent;
56class QSGNode;
57class QSGTransformNode;
58class QSGTextureProvider;
59class QQuickItemGrabResult;
60class QQuickPalette;
61
62class Q_QUICK_EXPORT QQuickItem : public QObject, public QQmlParserStatus
63{
64 Q_OBJECT
65 Q_INTERFACES(QQmlParserStatus)
66
67 Q_PROPERTY(QQuickItem *parent READ parentItem WRITE setParentItem NOTIFY parentChanged DESIGNABLE false FINAL)
68 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQmlListProperty<QObject> data READ data DESIGNABLE false)
69 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQmlListProperty<QObject> resources READ resources DESIGNABLE false)
70 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQmlListProperty<QQuickItem> children READ children NOTIFY childrenChanged DESIGNABLE false)
71
72 Q_PROPERTY(qreal x READ x WRITE setX NOTIFY xChanged BINDABLE bindableX FINAL)
73 Q_PROPERTY(qreal y READ y WRITE setY NOTIFY yChanged BINDABLE bindableY FINAL)
74 Q_PROPERTY(qreal z READ z WRITE setZ NOTIFY zChanged FINAL)
75 Q_PROPERTY(qreal width READ width WRITE setWidth NOTIFY widthChanged RESET resetWidth BINDABLE bindableWidth FINAL)
76 Q_PROPERTY(qreal height READ height WRITE setHeight NOTIFY heightChanged RESET resetHeight BINDABLE bindableHeight FINAL)
77
78 Q_PROPERTY(qreal opacity READ opacity WRITE setOpacity NOTIFY opacityChanged FINAL)
79 Q_PROPERTY(bool enabled READ isEnabled WRITE setEnabled NOTIFY enabledChanged)
80 Q_PROPERTY(bool visible READ isVisible WRITE setVisible NOTIFY visibleChanged FINAL)
81 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickPalette *palette READ palette WRITE setPalette RESET resetPalette NOTIFY paletteChanged REVISION(6, 0))
82 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQmlListProperty<QQuickItem> visibleChildren READ visibleChildren NOTIFY visibleChildrenChanged DESIGNABLE false)
83
84 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQmlListProperty<QQuickState> states READ states DESIGNABLE false)
85 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQmlListProperty<QQuickTransition> transitions READ transitions DESIGNABLE false)
86 Q_PROPERTY(QString state READ state WRITE setState NOTIFY stateChanged)
87 Q_PROPERTY(QRectF childrenRect READ childrenRect NOTIFY childrenRectChanged DESIGNABLE false FINAL)
88 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickAnchors * anchors READ anchors DESIGNABLE false CONSTANT FINAL)
89 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickAnchorLine left READ left CONSTANT FINAL)
90 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickAnchorLine right READ right CONSTANT FINAL)
91 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickAnchorLine horizontalCenter READ horizontalCenter CONSTANT FINAL)
92 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickAnchorLine top READ top CONSTANT FINAL)
93 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickAnchorLine bottom READ bottom CONSTANT FINAL)
94 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickAnchorLine verticalCenter READ verticalCenter CONSTANT FINAL)
95 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickAnchorLine baseline READ baseline CONSTANT FINAL)
96 Q_PROPERTY(qreal baselineOffset READ baselineOffset WRITE setBaselineOffset NOTIFY baselineOffsetChanged)
97
98 Q_PROPERTY(bool clip READ clip WRITE setClip NOTIFY clipChanged)
99
100 Q_PROPERTY(bool focus READ hasFocus WRITE setFocus NOTIFY focusChanged FINAL)
101 Q_PROPERTY(bool activeFocus READ hasActiveFocus NOTIFY activeFocusChanged FINAL)
102 Q_PROPERTY(bool activeFocusOnTab READ activeFocusOnTab WRITE setActiveFocusOnTab NOTIFY activeFocusOnTabChanged FINAL REVISION(2, 1))
103
104 Q_PROPERTY(Qt::FocusPolicy focusPolicy READ focusPolicy WRITE setFocusPolicy NOTIFY focusPolicyChanged REVISION(6, 7))
105
106 Q_PROPERTY(qreal rotation READ rotation WRITE setRotation NOTIFY rotationChanged)
107 Q_PROPERTY(qreal scale READ scale WRITE setScale NOTIFY scaleChanged)
108 Q_PROPERTY(TransformOrigin transformOrigin READ transformOrigin WRITE setTransformOrigin NOTIFY transformOriginChanged)
109 Q_PROPERTY(QPointF transformOriginPoint READ transformOriginPoint) // deprecated - see QTBUG-26423
110 Q_PROPERTY(QQmlListProperty<QQuickTransform> transform READ transform DESIGNABLE false FINAL)
111
112 Q_PROPERTY(bool smooth READ smooth WRITE setSmooth NOTIFY smoothChanged)
113 Q_PROPERTY(bool antialiasing READ antialiasing WRITE setAntialiasing NOTIFY antialiasingChanged RESET resetAntialiasing)
114 Q_PROPERTY(qreal implicitWidth READ implicitWidth WRITE setImplicitWidth NOTIFY implicitWidthChanged)
115 Q_PROPERTY(qreal implicitHeight READ implicitHeight WRITE setImplicitHeight NOTIFY implicitHeightChanged)
116 Q_PROPERTY(QObject *containmentMask READ containmentMask WRITE setContainmentMask NOTIFY containmentMaskChanged REVISION(2, 11))
117
118#if QT_CONFIG(quick_shadereffect)
119 Q_PRIVATE_PROPERTY(QQuickItem::d_func(), QQuickItemLayer *layer READ layer DESIGNABLE false CONSTANT FINAL)
120#endif
121
122 Q_CLASSINFO("DefaultProperty", "data")
123 Q_CLASSINFO("ParentProperty", "parent")
124 Q_CLASSINFO("qt_QmlJSWrapperFactoryMethod", "_q_createJSWrapper(QQmlV4ExecutionEnginePtr)")
125 QML_NAMED_ELEMENT(Item)
126 QML_ADDED_IN_VERSION(2, 0)
127
128public:
129 enum Flag {
130 ItemClipsChildrenToShape = 0x01,
131#if QT_CONFIG(im)
132 ItemAcceptsInputMethod = 0x02,
133#endif
134 ItemIsFocusScope = 0x04,
135 ItemHasContents = 0x08,
136 ItemAcceptsDrops = 0x10,
137 ItemIsViewport = 0x20,
138 ItemObservesViewport = 0x40,
139 // Remember to increment the size of QQuickItemPrivate::flags
140 };
141 Q_DECLARE_FLAGS(Flags, Flag)
142 Q_FLAG(Flags)
143
144 enum ItemChange {
145 ItemChildAddedChange, // value.item
146 ItemChildRemovedChange, // value.item
147 ItemSceneChange, // value.window
148 ItemVisibleHasChanged, // value.boolValue
149 ItemParentHasChanged, // value.item
150 ItemOpacityHasChanged, // value.realValue
151 ItemActiveFocusHasChanged, // value.boolValue
152 ItemRotationHasChanged, // value.realValue
153 ItemAntialiasingHasChanged, // value.boolValue
154 ItemDevicePixelRatioHasChanged, // value.realValue
155 ItemEnabledHasChanged, // value.boolValue
156 ItemScaleHasChanged, // value.realValue
157 ItemTransformHasChanged, // value.item
158 };
159 Q_ENUM(ItemChange)
160
161 union ItemChangeData {
162 ItemChangeData(QQuickItem *v) : item(v) {}
163 ItemChangeData(QQuickWindow *v) : window(v) {}
164 ItemChangeData(qreal v) : realValue(v) {}
165 ItemChangeData(bool v) : boolValue(v) {}
166
167 QQuickItem *item;
168 QQuickWindow *window;
169 qreal realValue;
170 bool boolValue;
171 };
172
173 enum TransformOrigin {
174 TopLeft, Top, TopRight,
175 Left, Center, Right,
176 BottomLeft, Bottom, BottomRight
177 };
178 Q_ENUM(TransformOrigin)
179
180 explicit QQuickItem(QQuickItem *parent = nullptr);
181 ~QQuickItem() override;
182
183 QQuickWindow *window() const;
184 QQuickItem *parentItem() const;
185 void setParentItem(QQuickItem *parent);
186 void stackBefore(const QQuickItem *);
187 void stackAfter(const QQuickItem *);
188
189 QRectF childrenRect();
190 QList<QQuickItem *> childItems() const;
191
192 bool clip() const;
193 void setClip(bool);
194
195 QString state() const;
196 void setState(const QString &);
197
198 qreal baselineOffset() const;
199 void setBaselineOffset(qreal);
200
201 QQmlListProperty<QQuickTransform> transform();
202
203 qreal x() const;
204 qreal y() const;
205 QPointF position() const;
206 void setX(qreal);
207 void setY(qreal);
208 void setPosition(const QPointF &);
209 QBindable<qreal> bindableX();
210 QBindable<qreal> bindableY();
211
212 qreal width() const;
213 void setWidth(qreal);
214 void resetWidth();
215 void setImplicitWidth(qreal);
216 qreal implicitWidth() const;
217 QBindable<qreal> bindableWidth();
218
219 qreal height() const;
220 void setHeight(qreal);
221 void resetHeight();
222 void setImplicitHeight(qreal);
223 qreal implicitHeight() const;
224 QBindable<qreal> bindableHeight();
225
226 QSizeF size() const;
227 void setSize(const QSizeF &size);
228
229 TransformOrigin transformOrigin() const;
230 void setTransformOrigin(TransformOrigin);
231 QPointF transformOriginPoint() const;
232 void setTransformOriginPoint(const QPointF &);
233
234 qreal z() const;
235 void setZ(qreal);
236
237 qreal rotation() const;
238 void setRotation(qreal);
239 qreal scale() const;
240 void setScale(qreal);
241
242 qreal opacity() const;
243 void setOpacity(qreal);
244
245 bool isVisible() const;
246 void setVisible(bool);
247
248 bool isEnabled() const;
249 void setEnabled(bool);
250
251 bool smooth() const;
252 void setSmooth(bool);
253
254 bool activeFocusOnTab() const;
255 void setActiveFocusOnTab(bool);
256
257 bool antialiasing() const;
258 void setAntialiasing(bool);
259 void resetAntialiasing();
260
261 Flags flags() const;
262 void setFlag(Flag flag, bool enabled = true);
263 void setFlags(Flags flags);
264
265 virtual QRectF boundingRect() const;
266 virtual QRectF clipRect() const;
267 QQuickItem *viewportItem() const;
268
269 bool hasActiveFocus() const;
270 bool hasFocus() const;
271 void setFocus(bool);
272 void setFocus(bool focus, Qt::FocusReason reason);
273 bool isFocusScope() const;
274 QQuickItem *scopedFocusItem() const;
275
276 Qt::FocusPolicy focusPolicy() const;
277 void setFocusPolicy(Qt::FocusPolicy policy);
278
279 bool isAncestorOf(const QQuickItem *child) const;
280
281 Qt::MouseButtons acceptedMouseButtons() const;
282 void setAcceptedMouseButtons(Qt::MouseButtons buttons);
283 bool acceptHoverEvents() const;
284 void setAcceptHoverEvents(bool enabled);
285 bool acceptTouchEvents() const;
286 void setAcceptTouchEvents(bool accept);
287
288#if QT_CONFIG(cursor)
289 QCursor cursor() const;
290 void setCursor(const QCursor &cursor);
291 void unsetCursor();
292#endif
293
294 bool isUnderMouse() const;
295 void grabMouse();
296 void ungrabMouse();
297 bool keepMouseGrab() const;
298 void setKeepMouseGrab(bool);
299 bool filtersChildMouseEvents() const;
300 void setFiltersChildMouseEvents(bool filter);
301
302 void grabTouchPoints(const QList<int> &ids);
303 void ungrabTouchPoints();
304 bool keepTouchGrab() const;
305 void setKeepTouchGrab(bool);
306
307 // implemented in qquickitemgrabresult.cpp
308 Q_REVISION(2, 4) Q_INVOKABLE bool grabToImage(const QJSValue &callback, const QSize &targetSize = QSize());
309 QSharedPointer<QQuickItemGrabResult> grabToImage(const QSize &targetSize = QSize());
310
311 Q_INVOKABLE virtual bool contains(const QPointF &point) const;
312 QObject *containmentMask() const;
313 void setContainmentMask(QObject *mask);
314
315 QTransform itemTransform(QQuickItem *, bool *) const;
316 QPointF mapToScene(const QPointF &point) const;
317 QRectF mapRectToItem(const QQuickItem *item, const QRectF &rect) const;
318 QRectF mapRectToScene(const QRectF &rect) const;
319 QPointF mapFromScene(const QPointF &point) const;
320 QRectF mapRectFromItem(const QQuickItem *item, const QRectF &rect) const;
321 QRectF mapRectFromScene(const QRectF &rect) const;
322
323 void polish();
324
325#if QT_DEPRECATED_SINCE(6, 5)
326 QT_DEPRECATED_VERSION_X_6_5("Use typed overload or mapRectFromItem")
327 void mapFromItem(QQmlV4FunctionPtr) const;
328#endif
329 Q_INVOKABLE QPointF mapFromItem(const QQuickItem *item, const QPointF &point) const;
330 // overloads mainly exist for QML
331 Q_INVOKABLE QPointF mapFromItem(const QQuickItem *item, qreal x, qreal y);
332 Q_INVOKABLE QRectF mapFromItem(const QQuickItem *item, const QRectF &rect) const;
333 Q_INVOKABLE QRectF mapFromItem(const QQuickItem *item, qreal x, qreal y, qreal width, qreal height) const;
334
335#if QT_DEPRECATED_SINCE(6, 5)
336 QT_DEPRECATED_VERSION_X_6_5("Use typed overload or mapRectToItem")
337 void mapToItem(QQmlV4FunctionPtr) const;
338#endif
339 Q_INVOKABLE QPointF mapToItem(const QQuickItem *item, const QPointF &point) const;
340 // overloads mainly exist for QML
341 Q_INVOKABLE QPointF mapToItem(const QQuickItem *item, qreal x, qreal y);
342 Q_INVOKABLE QRectF mapToItem(const QQuickItem *item, const QRectF &rect) const;
343 Q_INVOKABLE QRectF mapToItem(const QQuickItem *item, qreal x, qreal y, qreal width, qreal height) const;
344
345#if QT_DEPRECATED_SINCE(6, 5)
346 QT_DEPRECATED_VERSION_X_6_5("Use the typed overload")
347 Q_REVISION(2, 7) void mapFromGlobal(QQmlV4FunctionPtr) const;
348#endif
349 Q_REVISION(2, 7) Q_INVOKABLE QPointF mapFromGlobal(qreal x, qreal y) const;
350 // overload mainly exists for QML
351 Q_REVISION(2, 7) Q_INVOKABLE QPointF mapFromGlobal(const QPointF &point) const;
352
353#if QT_DEPRECATED_SINCE(6, 5)
354 QT_DEPRECATED_VERSION_X_6_5("Use the typed overload")
355 Q_REVISION(2, 7) void mapToGlobal(QQmlV4FunctionPtr) const;
356#endif
357 Q_REVISION(2, 7) Q_INVOKABLE QPointF mapToGlobal(qreal x, qreal y) const;
358 // overload only exist for QML
359 Q_REVISION(2, 7) Q_INVOKABLE QPointF mapToGlobal(const QPointF &point) const;
360
361 Q_INVOKABLE void forceActiveFocus();
362 Q_INVOKABLE void forceActiveFocus(Qt::FocusReason reason);
363 Q_REVISION(2, 1) Q_INVOKABLE QQuickItem *nextItemInFocusChain(bool forward = true);
364 Q_INVOKABLE QQuickItem *childAt(qreal x, qreal y) const;
365 Q_REVISION(6, 3) Q_INVOKABLE void ensurePolished();
366
367 Q_REVISION(6, 3) Q_INVOKABLE void dumpItemTree() const;
368
369#if QT_CONFIG(im)
370 virtual QVariant inputMethodQuery(Qt::InputMethodQuery query) const;
371#endif
372
373 struct UpdatePaintNodeData {
374 QSGTransformNode *transformNode;
375 private:
376 friend class QQuickWindowPrivate;
377 UpdatePaintNodeData();
378 };
379
380 virtual bool isTextureProvider() const;
381 virtual QSGTextureProvider *textureProvider() const;
382
383public Q_SLOTS:
384 void update();
385
386Q_SIGNALS:
387 void childrenRectChanged(const QRectF &);
388 void baselineOffsetChanged(qreal);
389 void stateChanged(const QString &);
390 void focusChanged(bool);
391 void activeFocusChanged(bool);
392 Q_REVISION(6, 7) void focusPolicyChanged(Qt::FocusPolicy);
393 Q_REVISION(2, 1) void activeFocusOnTabChanged(bool);
394 void parentChanged(QQuickItem *);
395 void transformOriginChanged(TransformOrigin);
396 void smoothChanged(bool);
397 void antialiasingChanged(bool);
398 void clipChanged(bool);
399 Q_REVISION(2, 1) void windowChanged(QQuickWindow* window);
400
401 void childrenChanged();
402 void opacityChanged();
403 void enabledChanged();
404 void visibleChanged();
405 void visibleChildrenChanged();
406 void rotationChanged();
407 void scaleChanged();
408
409 void xChanged();
410 void yChanged();
411 void widthChanged();
412 void heightChanged();
413 void zChanged();
414 void implicitWidthChanged();
415 void implicitHeightChanged();
416 Q_REVISION(2, 11) void containmentMaskChanged();
417
418 Q_REVISION(6, 0) void paletteChanged();
419 Q_REVISION(6, 0) void paletteCreated();
420
421protected:
422 bool event(QEvent *) override;
423
424 bool isComponentComplete() const;
425 virtual void itemChange(ItemChange, const ItemChangeData &);
426 virtual void geometryChange(const QRectF &newGeometry, const QRectF &oldGeometry);
427
428#if QT_CONFIG(im)
429 void updateInputMethod(Qt::InputMethodQueries queries = Qt::ImQueryInput);
430#endif
431
432 bool widthValid() const; // ### better name?
433 bool heightValid() const; // ### better name?
434 void setImplicitSize(qreal, qreal);
435
436 void classBegin() override;
437 void componentComplete() override;
438
439 virtual void keyPressEvent(QKeyEvent *event);
440 virtual void keyReleaseEvent(QKeyEvent *event);
441#if QT_CONFIG(im)
442 virtual void inputMethodEvent(QInputMethodEvent *);
443#endif
444 virtual void focusInEvent(QFocusEvent *);
445 virtual void focusOutEvent(QFocusEvent *);
446 virtual void mousePressEvent(QMouseEvent *event);
447 virtual void mouseMoveEvent(QMouseEvent *event);
448 virtual void mouseReleaseEvent(QMouseEvent *event);
449 virtual void mouseDoubleClickEvent(QMouseEvent *event);
450 virtual void mouseUngrabEvent(); // XXX todo - params?
451 virtual void touchUngrabEvent();
452#if QT_CONFIG(wheelevent)
453 virtual void wheelEvent(QWheelEvent *event);
454#endif
455 virtual void touchEvent(QTouchEvent *event);
456 virtual void hoverEnterEvent(QHoverEvent *event);
457 virtual void hoverMoveEvent(QHoverEvent *event);
458 virtual void hoverLeaveEvent(QHoverEvent *event);
459#if QT_CONFIG(quick_draganddrop)
460 virtual void dragEnterEvent(QDragEnterEvent *);
461 virtual void dragMoveEvent(QDragMoveEvent *);
462 virtual void dragLeaveEvent(QDragLeaveEvent *);
463 virtual void dropEvent(QDropEvent *);
464#endif
465 virtual bool childMouseEventFilter(QQuickItem *, QEvent *);
466#if QT_VERSION >= QT_VERSION_CHECK(7, 0, 0)
467 virtual bool contextMenuEvent(QContextMenuEvent *event);
468#endif
469
470 virtual QSGNode *updatePaintNode(QSGNode *, UpdatePaintNodeData *);
471 virtual void releaseResources();
472 virtual void updatePolish();
473
474 QQuickItem(QQuickItemPrivate &dd, QQuickItem *parent = nullptr);
475
476private:
477 Q_PRIVATE_SLOT(d_func(), void _q_resourceObjectDeleted(QObject *))
478 Q_PRIVATE_SLOT(d_func(), quint64 _q_createJSWrapper(QQmlV4ExecutionEnginePtr))
479
480 friend class QQuickWindowPrivate;
481 friend class QQuickDeliveryAgentPrivate;
482 friend class QSGRenderer;
483 friend class QAccessibleQuickItem;
484 friend class QQuickAccessibleAttached;
485 friend class QQuickAnchorChanges;
486#ifndef QT_NO_DEBUG_STREAM
487 friend Q_QUICK_EXPORT QDebug operator<<(QDebug debug, QQuickItem *item);
488#endif
489
490 Q_DISABLE_COPY(QQuickItem)
491 Q_DECLARE_PRIVATE(QQuickItem)
492};
493
494Q_DECLARE_OPERATORS_FOR_FLAGS(QQuickItem::Flags)
495
496#ifndef Q_QDOC
497template <> inline QQuickItem *qobject_cast<QQuickItem *>(QObject *o)
498{
499 if (!o || !o->isQuickItemType())
500 return nullptr;
501 return static_cast<QQuickItem *>(o);
502}
503template <> inline const QQuickItem *qobject_cast<const QQuickItem *>(const QObject *o)
504{
505 if (!o || !o->isQuickItemType())
506 return nullptr;
507 return static_cast<const QQuickItem *>(o);
508}
509#endif // !Q_QDOC
510
511#ifndef QT_NO_DEBUG_STREAM
512QDebug Q_QUICK_EXPORT operator<<(QDebug debug,
513#if QT_VERSION >= QT_VERSION_CHECK(7, 0, 0)
514 const
515#endif
516 QQuickItem *item);
517#endif // QT_NO_DEBUG_STREAM
518
519QT_END_NAMESPACE
520
521#endif // QQUICKITEM_H
522

source code of qtdeclarative/src/quick/items/qquickitem.h