Flickable: handle child mouse ungrab when hidden or disabled

If Flickable got hidden while a child had mouse grab, it ignored the
mouse ungrab event of the child mouse grabber, and got therefore stuck
in pressed state. Consequently, item view transitions were not executed
since the item view though it was being pressed.

Task-number: QTBUG-58453
Change-Id: I76f9f3190c3a95a2fafdce036d69ea1dc8127434
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@qt.io>

3 files changed, 37 insertions, 1 deletions

diff --git a/src/quick/items/qquickflickable.cpp b/src/quick/items/qquickflickable.cpp
index 1e778306e0..537367b3a3 100644
--- a/src/quick/items/qquickflickable.cpp
+++ b/src/quick/items/qquickflickable.cpp
@@ -2307,8 +2307,11 @@ bool QQuickFlickable::filterMouseEvent(QQuickItem *receiver, QMouseEvent *event)
 bool QQuickFlickable::childMouseEventFilter(QQuickItem *i, QEvent *e)
 {
     Q_D(QQuickFlickable);
-    if (!isVisible() || !isEnabled() || !isInteractive())
+    if (!isVisible() || !isEnabled() || !isInteractive()) {
+        d->cancelInteraction();
         return QQuickItem::childMouseEventFilter(i, e);
+    }
+
     switch (e->type()) {
     case QEvent::MouseButtonPress:
     case QEvent::MouseMove:
diff --git a/tests/auto/quick/qquickflickable/data/hide.qml b/tests/auto/quick/qquickflickable/data/hide.qml
new file mode 100644
index 0000000000..ab520549e2
--- /dev/null
+++ b/tests/auto/quick/qquickflickable/data/hide.qml
@@ -0,0 +1,13 @@
+import QtQuick 2.0
+
+Flickable {
+    id: flickable
+    width: 200; height: 200
+    contentWidth: 400; contentHeight: 400
+
+    MouseArea {
+        objectName: "mouseArea"
+        width: 400; height: 400
+        onDoubleClicked: flickable.visible = false
+    }
+}
diff --git a/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp b/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp
index 942e99018f..2555322e3e 100644
--- a/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp
+++ b/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp
@@ -80,6 +80,7 @@ private slots:
     void disabled();
     void flickVelocity();
     void margins();
+    void cancelOnHide();
     void cancelOnMouseGrab();
     void clickAndDragWhenTransformed();
     void flickTwiceUsingTouches();
@@ -1422,6 +1423,25 @@ void tst_qquickflickable::margins()
     delete root;
 }
 
+void tst_qquickflickable::cancelOnHide()
+{
+    QScopedPointer<QQuickView> window(new QQuickView);
+    window->setSource(testFileUrl("hide.qml"));
+    QTRY_COMPARE(window->status(), QQuickView::Ready);
+    QQuickViewTestUtil::centerOnScreen(window.data());
+    QQuickViewTestUtil::moveMouseAway(window.data());
+    window->show();
+    QVERIFY(QTest::qWaitForWindowActive(window.data()));
+    QVERIFY(window->rootObject());
+
+    QQuickFlickable *flickable = qobject_cast<QQuickFlickable*>(window->rootObject());
+    QVERIFY(flickable);
+
+    QTest::mouseDClick(window.data(), Qt::LeftButton);
+    QVERIFY(!flickable->isVisible());
+    QVERIFY(!QQuickFlickablePrivate::get(flickable)->pressed);
+}
+
 void tst_qquickflickable::cancelOnMouseGrab()
 {
     QScopedPointer<QQuickView> window(new QQuickView);