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36
37#include "qquickitemgroup_p.h"
38
39#include <QtQuick/private/qquickimplicitsizeitem_p_p.h>
40
41QT_BEGIN_NAMESPACE
42
43QQuickItemGroup::QQuickItemGroup(QQuickItem *parent)
44 : QQuickImplicitSizeItem(*(new QQuickImplicitSizeItemPrivate), parent)
45{
46}
47
48QQuickItemGroup::~QQuickItemGroup()
49{
50 const auto children = childItems();
51 for (QQuickItem *child : children)
52 unwatch(item: child);
53}
54
55void QQuickItemGroup::watch(QQuickItem *item)
56{
57 QQuickItemPrivate::get(item)->addItemChangeListener(listener: this, types: QQuickItemPrivate::ImplicitWidth | QQuickItemPrivate::ImplicitHeight);
58}
59
60void QQuickItemGroup::unwatch(QQuickItem *item)
61{
62 QQuickItemPrivate::get(item)->removeItemChangeListener(this, types: QQuickItemPrivate::ImplicitWidth | QQuickItemPrivate::ImplicitHeight);
63}
64
65QSizeF QQuickItemGroup::calculateImplicitSize() const
66{
67 qreal width = 0;
68 qreal height = 0;
69 const auto children = childItems();
70 for (QQuickItem *child : children) {
71 width = qMax(a: width, b: child->implicitWidth());
72 height = qMax(a: height, b: child->implicitHeight());
73 }
74 return QSizeF(width, height);
75}
76
77void QQuickItemGroup::updateImplicitSize()
78{
79 QSizeF size = calculateImplicitSize();
80 setImplicitSize(size.width(), size.height());
81}
82
83void QQuickItemGroup::itemChange(ItemChange change, const ItemChangeData &data)
84{
85 QQuickImplicitSizeItem::itemChange(change, data);
86 switch (change) {
87 case ItemChildAddedChange:
88 watch(item: data.item);
89 data.item->setSize(QSizeF(width(), height()));
90 updateImplicitSize();
91 break;
92 case ItemChildRemovedChange:
93 unwatch(item: data.item);
94 updateImplicitSize();
95 break;
96 default:
97 break;
98 }
99}
100
101void QQuickItemGroup::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)
102{
103 QQuickImplicitSizeItem::geometryChanged(newGeometry, oldGeometry);
104
105 if (newGeometry.size() != oldGeometry.size()) {
106 const auto children = childItems();
107 for (QQuickItem *child : children)
108 child->setSize(newGeometry.size());
109 }
110}
111
112void QQuickItemGroup::itemImplicitWidthChanged(QQuickItem *)
113{
114 setImplicitWidth(calculateImplicitSize().width());
115}
116
117void QQuickItemGroup::itemImplicitHeightChanged(QQuickItem *)
118{
119 setImplicitHeight(calculateImplicitSize().height());
120}
121
122QT_END_NAMESPACE
123

source code of qtquickcontrols2/src/quickcontrols2/qquickitemgroup.cpp