Move visual overlay background management to QQuickPopup

During the early days, there was only one visual overlay background
dimmer, so QQuickOverlay was the natural choice to manage it. It was
soon realized that multiple modal popups and drawers needed each their
own background dimming. Now the implementation becomes simpler when
each popup manages its own background dimming. This paves the road for
the upcoming changes making it possible to provide background dimming
without ApplicationWindow.

Task-number: QTBUG-61336
Change-Id: I621db4efe4aa74c147f81f7aee8affebddb00d49
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>

1 files changed, 1 insertions, 122 deletions

diff --git a/src/quicktemplates2/qquickoverlay.cpp b/src/quicktemplates2/qquickoverlay.cpp
index a4aaa60d..8ea97069 100644
--- a/src/quicktemplates2/qquickoverlay.cpp
+++ b/src/quicktemplates2/qquickoverlay.cpp
@@ -47,103 +47,6 @@
 
 QT_BEGIN_NAMESPACE
 
-void QQuickOverlayPrivate::popupAboutToShow()
-{
-    Q_Q(QQuickOverlay);
-    QQuickPopup *popup = qobject_cast<QQuickPopup *>(q->sender());
-    if (!popup || !popup->dim())
-        return;
-
-    // use QQmlProperty instead of QQuickItem::setOpacity() to trigger QML Behaviors
-    QQuickPopupPrivate *p = QQuickPopupPrivate::get(popup);
-    if (p->dimmer)
-        QQmlProperty::write(p->dimmer, QStringLiteral("opacity"), 1.0);
-}
-
-void QQuickOverlayPrivate::popupAboutToHide()
-{
-    Q_Q(QQuickOverlay);
-    QQuickPopup *popup = qobject_cast<QQuickPopup *>(q->sender());
-    if (!popup || !popup->dim())
-        return;
-
-    // use QQmlProperty instead of QQuickItem::setOpacity() to trigger QML Behaviors
-    QQuickPopupPrivate *p = QQuickPopupPrivate::get(popup);
-    if (p->dimmer)
-        QQmlProperty::write(p->dimmer, QStringLiteral("opacity"), 0.0);
-}
-
-static QQuickItem *createDimmer(QQmlComponent *component, QQuickPopup *popup, QQuickItem *parent)
-{
-    QQuickItem *item = nullptr;
-    if (component) {
-        QQmlContext *creationContext = component->creationContext();
-        if (!creationContext)
-            creationContext = qmlContext(parent);
-        QQmlContext *context = new QQmlContext(creationContext, parent);
-        context->setContextObject(popup);
-        item = qobject_cast<QQuickItem*>(component->beginCreate(context));
-    }
-
-    // when there is no overlay component available (with plain QQuickWindow),
-    // use a plain QQuickItem as a fallback to block hover events
-    if (!item && popup->isModal())
-        item = new QQuickItem;
-
-    if (item) {
-        item->setOpacity(popup->isVisible() ? 1.0 : 0.0);
-        item->setParentItem(parent);
-        item->stackBefore(popup->popupItem());
-        item->setZ(popup->z());
-        if (popup->isModal()) {
-            item->setAcceptedMouseButtons(Qt::AllButtons);
-#if QT_CONFIG(cursor)
-            item->setCursor(Qt::ArrowCursor);
-#endif
-#if QT_CONFIG(quicktemplates2_hover)
-            // TODO: switch to QStyleHints::useHoverEffects in Qt 5.8
-            item->setAcceptHoverEvents(true);
-            // item->setAcceptHoverEvents(QGuiApplication::styleHints()->useHoverEffects());
-            // connect(QGuiApplication::styleHints(), &QStyleHints::useHoverEffectsChanged, item, &QQuickItem::setAcceptHoverEvents);
-#endif
-        }
-        if (component)
-            component->completeCreate();
-    }
-    return item;
-}
-
-void QQuickOverlayPrivate::createOverlay(QQuickPopup *popup)
-{
-    Q_Q(QQuickOverlay);
-    QQuickPopupPrivate *p = QQuickPopupPrivate::get(popup);
-    if (!p->dimmer)
-        p->dimmer = createDimmer(popup->isModal() ? modal : modeless, popup, q);
-    p->resizeOverlay();
-}
-
-void QQuickOverlayPrivate::destroyOverlay(QQuickPopup *popup)
-{
-    QQuickPopupPrivate *p = QQuickPopupPrivate::get(popup);
-    if (p->dimmer) {
-        p->dimmer->setParentItem(nullptr);
-        p->dimmer->deleteLater();
-        p->dimmer = nullptr;
-    }
-}
-
-void QQuickOverlayPrivate::toggleOverlay()
-{
-    Q_Q(QQuickOverlay);
-    QQuickPopup *popup = qobject_cast<QQuickPopup *>(q->sender());
-    if (!popup)
-        return;
-
-    destroyOverlay(popup);
-    if (popup->dim())
-        createOverlay(popup);
-}
-
 QVector<QQuickPopup *> QQuickOverlayPrivate::stackingOrderPopups() const
 {
     const QList<QQuickItem *> children = paintOrderChildItems();
@@ -423,32 +326,8 @@ void QQuickOverlay::itemChange(ItemChange change, const ItemChangeData &data)
     Q_D(QQuickOverlay);
     QQuickItem::itemChange(change, data);
 
-    QQuickPopup *popup = nullptr;
-    if (change == ItemChildAddedChange || change == ItemChildRemovedChange) {
-        popup = qobject_cast<QQuickPopup *>(data.item->parent());
+    if (change == ItemChildAddedChange || change == ItemChildRemovedChange)
         setVisible(!d->allDrawers.isEmpty() || !childItems().isEmpty());
-    }
-    if (!popup)
-        return;
-
-    if (change == ItemChildAddedChange) {
-        if (popup->dim())
-            d->createOverlay(popup);
-        QObjectPrivate::connect(popup, &QQuickPopup::dimChanged, d, &QQuickOverlayPrivate::toggleOverlay);
-        QObjectPrivate::connect(popup, &QQuickPopup::modalChanged, d, &QQuickOverlayPrivate::toggleOverlay);
-        if (!qobject_cast<QQuickDrawer *>(popup)) {
-            QObjectPrivate::connect(popup, &QQuickPopup::aboutToShow, d, &QQuickOverlayPrivate::popupAboutToShow);
-            QObjectPrivate::connect(popup, &QQuickPopup::aboutToHide, d, &QQuickOverlayPrivate::popupAboutToHide);
-        }
-    } else if (change == ItemChildRemovedChange) {
-        d->destroyOverlay(popup);
-        QObjectPrivate::disconnect(popup, &QQuickPopup::dimChanged, d, &QQuickOverlayPrivate::toggleOverlay);
-        QObjectPrivate::disconnect(popup, &QQuickPopup::modalChanged, d, &QQuickOverlayPrivate::toggleOverlay);
-        if (!qobject_cast<QQuickDrawer *>(popup)) {
-            QObjectPrivate::disconnect(popup, &QQuickPopup::aboutToShow, d, &QQuickOverlayPrivate::popupAboutToShow);
-            QObjectPrivate::disconnect(popup, &QQuickPopup::aboutToHide, d, &QQuickOverlayPrivate::popupAboutToHide);
-        }
-    }
 }
 
 void QQuickOverlay::geometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry)