StackView: add removed() attached signal

This provides an opportunity for users to destroy items that StackView
doesn't, like objects that are pushed as Items.

[ChangeLog][Controls][StackView] Added StackView.removed() attached
signal to provide a way to delete items that StackView won't.

Task-number: QTBUG-55405
Change-Id: I59096efaf1a95d36451fbf1f46b8f68ee96c20de
Reviewed-by: J-P Nurmi <jpnurmi@qt.io>

3 files changed, 22 insertions, 1 deletions

diff --git a/src/quicktemplates2/qquickstackview.cpp b/src/quicktemplates2/qquickstackview.cpp
index df163089..040eff1b 100644
--- a/src/quicktemplates2/qquickstackview.cpp
+++ b/src/quicktemplates2/qquickstackview.cpp
@@ -1092,4 +1092,21 @@ QQuickStackView::Status QQuickStackAttached::status() const
     \sa status
 */
 
+/*!
+    \qmlattachedsignal QtQuick.Controls::StackView::removed()
+    \since QtQuick.Controls 2.1
+
+    This attached signal is emitted when the item it's attached to has been
+    removed from the stack. It can be used to safely destroy an Item that was
+    pushed onto the stack, for example:
+
+    \code
+    Item {
+        StackView.onRemoved: destroy() // Will be destroyed sometime after this call.
+    }
+    \endcode
+
+    \sa status
+*/
+
 QT_END_NAMESPACE
diff --git a/src/quicktemplates2/qquickstackview_p.cpp b/src/quicktemplates2/qquickstackview_p.cpp
index 0f5674c2..438b4269 100644
--- a/src/quicktemplates2/qquickstackview_p.cpp
+++ b/src/quicktemplates2/qquickstackview_p.cpp
@@ -85,6 +85,7 @@ QQuickStackElement::~QQuickStackElement()
     if (ownComponent)
         delete component;
 
+    QQuickStackAttached *attached = attachedStackObject(this);
     if (item) {
         if (ownItem) {
             item->setParentItem(nullptr);
@@ -99,13 +100,15 @@ QQuickStackElement::~QQuickStackElement()
             if (item->parentItem() != originalParent) {
                 item->setParentItem(originalParent);
             } else {
-                QQuickStackAttached *attached = attachedStackObject(this);
                 if (attached)
                     QQuickStackAttachedPrivate::get(attached)->itemParentChanged(item, nullptr);
             }
         }
     }
 
+    if (attached)
+        emit attached->removed();
+
     delete context;
 }
 
diff --git a/src/quicktemplates2/qquickstackview_p.h b/src/quicktemplates2/qquickstackview_p.h
index d8b6ce7c..9bf60183 100644
--- a/src/quicktemplates2/qquickstackview_p.h
+++ b/src/quicktemplates2/qquickstackview_p.h
@@ -182,6 +182,7 @@ Q_SIGNALS:
     /*Q_REVISION(1)*/ void activating();
     /*Q_REVISION(1)*/ void deactivated();
     /*Q_REVISION(1)*/ void deactivating();
+    /*Q_REVISION(1)*/ void removed();
 
 private:
     Q_DISABLE_COPY(QQuickStackAttached)