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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 
47 QT_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  */
reparentChildItems(QGraphicsItem * newParent)54 void 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("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 
getMargin(qreal * result,qreal userMargin,QStyle::PixelMetric pm) const83 void 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(pm, nullptr);
101         }
102     }
103 }
104 
visualDirection() const105 Qt::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 
removeLayoutItemFromLayout(QGraphicsLayout * lay,QGraphicsLayoutItem * layoutItem)114 static 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(static_cast<QGraphicsLayout*>(child), layoutItem))
123                 return true;
124         } else if (child == layoutItem) {
125             lay->removeAt(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 */
addChildLayoutItem(QGraphicsLayoutItem * layoutItem)143 void QGraphicsLayoutPrivate::addChildLayoutItem(QGraphicsLayoutItem *layoutItem)
144 {
145     Q_Q(QGraphicsLayout);
146     if (QGraphicsLayoutItem *maybeLayout = layoutItem->parentLayoutItem()) {
147         if (maybeLayout->isLayout())
148             removeLayoutItemFromLayout(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(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("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 
activateRecursive(QGraphicsLayoutItem * item)175 void 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(childItem);
191         }
192         layout->d_func()->activated = true;
193     }
194 }
195 
196 QT_END_NAMESPACE
197