/*!
Activates the layout, causing all items in the layout to be immediately
rearranged. This function is based on calling count() and itemAt(), and
then calling setGeometry() on all items sequentially. When activated,
the layout will adjust its geometry to its parent's contentsRect().
The parent will then invalidate any layout of its own.
If called in sequence or recursively, e.g., by one of the arranged items
in response to being resized, this function will do nothing.
Note that the layout is free to use geometry caching to optimize this
process. To forcefully invalidate any such cache, you can call
invalidate() before calling activate().
\sa invalidate()
*/
void QGraphicsLayout::activate()
{
Q_D(QGraphicsLayout);
if (d->activated)
return;
d->activateRecursive(this);
// we don't call activate on a sublayout, but somebody might.
// Therefore, we walk to the parentitem of the toplevel layout.
QGraphicsLayoutItem *parentItem = this;
while (parentItem && parentItem->isLayout())
parentItem = parentItem->parentLayoutItem();
if (!parentItem)
return;
Q_ASSERT(!parentItem->isLayout());
if (QGraphicsLayout::instantInvalidatePropagation()) {
QGraphicsWidget *parentWidget = static_cast<QGraphicsWidget*>(parentItem);
if (!parentWidget->parentLayoutItem()) {
// we've reached the topmost widget, resize it
bool wasResized = parentWidget->testAttribute(Qt::WA_Resized);
parentWidget->resize(parentWidget->size());
parentWidget->setAttribute(Qt::WA_Resized, wasResized);
}
setGeometry(parentItem->contentsRect()); // relayout children
} else {
setGeometry(parentItem->contentsRect()); // relayout children
parentLayoutItem()->updateGeometry();
}
}
/*!
Destroys the QGraphicsWidget instance.
*/
QGraphicsWidget::~QGraphicsWidget()
{
Q_D(QGraphicsWidget);
#ifndef QT_NO_ACTION
// Remove all actions from this widget
for (int i = 0; i < d->actions.size(); ++i) {
QActionPrivate *apriv = d->actions.at(i)->d_func();
apriv->graphicsWidgets.removeAll(this);
}
d->actions.clear();
#endif
if (QGraphicsScene *scn = scene()) {
QGraphicsScenePrivate *sceneD = scn->d_func();
if (sceneD->tabFocusFirst == this)
sceneD->tabFocusFirst = (d->focusNext == this ? 0 : d->focusNext);
}
d->focusPrev->d_func()->focusNext = d->focusNext;
d->focusNext->d_func()->focusPrev = d->focusPrev;
// Play it really safe
d->focusNext = this;
d->focusPrev = this;
clearFocus();
//we check if we have a layout previously
if (d->layout) {
QGraphicsLayout *temp = d->layout;
foreach (QGraphicsItem * item, childItems()) {
// In case of a custom layout which doesn't remove and delete items, we ensure that
// the parent layout item does not point to the deleted layout. This code is here to
// avoid regression from 4.4 to 4.5, because according to 4.5 docs it is not really needed.
if (item->isWidget()) {
QGraphicsWidget *widget = static_cast<QGraphicsWidget *>(item);
if (widget->parentLayoutItem() == d->layout)
widget->setParentLayoutItem(0);
}
}
d->layout = 0;
delete temp;
}