Make QQuickOverlay resize itself

This prepares QQuickOverlay to be usable with a plain QQuickWindow,
for which we cannot override resizeEvent().

Change-Id: Ib021c510539b134477bb8d532787721a5ac7fca4
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

3 files changed, 23 insertions, 8 deletions

diff --git a/src/quicktemplates2/qquickapplicationwindow.cpp b/src/quicktemplates2/qquickapplicationwindow.cpp
index 2706d9b6..bf903b8a 100644
--- a/src/quicktemplates2/qquickapplicationwindow.cpp
+++ b/src/quicktemplates2/qquickapplicationwindow.cpp
@@ -157,12 +157,6 @@ void QQuickApplicationWindowPrivate::relayout()
     content->setWidth(q->width());
     content->setHeight(q->height() - hh - fh);
 
-    if (overlay) {
-        overlay->setWidth(q->width());
-        overlay->setHeight(q->height());
-        overlay->stackAfter(content);
-    }
-
     if (header) {
         header->setY(-hh);
         QQuickItemPrivate *p = QQuickItemPrivate::get(header);
@@ -484,7 +478,7 @@ QQuickOverlay *QQuickApplicationWindow::overlay() const
     QQuickApplicationWindowPrivate *d = const_cast<QQuickApplicationWindowPrivate *>(d_func());
     if (!d->overlay) {
         d->overlay = new QQuickOverlay(QQuickWindow::contentItem());
-        d->relayout();
+        d->overlay->stackAfter(QQuickApplicationWindow::contentItem());
     }
     return d->overlay;
 }
diff --git a/src/quicktemplates2/qquickoverlay.cpp b/src/quicktemplates2/qquickoverlay.cpp
index 5dd92a26..c5818b90 100644
--- a/src/quicktemplates2/qquickoverlay.cpp
+++ b/src/quicktemplates2/qquickoverlay.cpp
@@ -41,10 +41,11 @@
 #include <QtQml/qqmlproperty.h>
 #include <QtQml/qqmlcomponent.h>
 #include <QtQuick/private/qquickitem_p.h>
+#include <QtQuick/private/qquickitemchangelistener_p.h>
 
 QT_BEGIN_NAMESPACE
 
-class QQuickOverlayPrivate : public QQuickItemPrivate
+class QQuickOverlayPrivate : public QQuickItemPrivate, public QQuickItemChangeListener
 {
     Q_DECLARE_PUBLIC(QQuickOverlay)
 
@@ -61,6 +62,8 @@ public:
 
     QVector<QQuickPopup *> stackingOrderPopups() const;
 
+    void itemGeometryChanged(QQuickItem *item, const QRectF &newGeometry, const QRectF &oldGeometry) override;
+
     QQmlComponent *modal;
     QQmlComponent *modeless;
     QVector<QQuickDrawer *> drawers;
@@ -179,6 +182,12 @@ QVector<QQuickPopup *> QQuickOverlayPrivate::stackingOrderPopups() const
     return popups;
 }
 
+void QQuickOverlayPrivate::itemGeometryChanged(QQuickItem *, const QRectF &newGeometry, const QRectF &)
+{
+    Q_Q(QQuickOverlay);
+    q->setSize(newGeometry.size());
+}
+
 QQuickOverlayPrivate::QQuickOverlayPrivate() :
     modal(nullptr),
     modeless(nullptr),
@@ -189,10 +198,21 @@ QQuickOverlayPrivate::QQuickOverlayPrivate() :
 QQuickOverlay::QQuickOverlay(QQuickItem *parent)
     : QQuickItem(*(new QQuickOverlayPrivate), parent)
 {
+    Q_D(QQuickOverlay);
     setZ(1000001); // DefaultWindowDecoration+1
     setAcceptedMouseButtons(Qt::AllButtons);
     setFiltersChildMouseEvents(true);
     setVisible(false);
+
+    if (parent)
+        QQuickItemPrivate::get(parent)->addItemChangeListener(d, QQuickItemPrivate::Geometry);
+}
+
+QQuickOverlay::~QQuickOverlay()
+{
+    Q_D(QQuickOverlay);
+    if (QQuickItem *parent = parentItem())
+        QQuickItemPrivate::get(parent)->removeItemChangeListener(d, QQuickItemPrivate::Geometry);
 }
 
 QQmlComponent *QQuickOverlay::modal() const
diff --git a/src/quicktemplates2/qquickoverlay_p.h b/src/quicktemplates2/qquickoverlay_p.h
index 99d7ba75..480a5a6a 100644
--- a/src/quicktemplates2/qquickoverlay_p.h
+++ b/src/quicktemplates2/qquickoverlay_p.h
@@ -64,6 +64,7 @@ class Q_QUICKTEMPLATES2_PRIVATE_EXPORT QQuickOverlay : public QQuickItem
 
 public:
     explicit QQuickOverlay(QQuickItem *parent = nullptr);
+    ~QQuickOverlay();
 
     QQmlComponent *modal() const;
     void setModal(QQmlComponent *modal);