Remove mouse grabber if touch used for mouse emulation has been grabbed

If an item grabs a touch that is currently being used for mouse pointer
emulation, the current mouse grabber should lose the mouse as mouse
events will no longer be generated from that touch point.

Example of what happens without this patch:
-User touches a MouseArea. It gets pressed.
-Some other item grabs that touch.
-This touch eventually ends.
-The MouseArea would still be pressed.
And what will happens instead after this patch:
-User touches a MouseArea. It gets pressed.
-Some other item grabs that touch.
-The MouseArea gets canceled and released
-This touch eventually ends.

Change-Id: I24114f18be564553a4a768243bb20379affe7a8f
Reviewed-by: Shawn Rutledge <shawn.rutledge@digia.com>

2 files changed, 97 insertions, 10 deletions

diff --git a/tests/auto/quick/touchmouse/data/twosiblingitems.qml b/tests/auto/quick/touchmouse/data/twosiblingitems.qml
new file mode 100644
index 0000000000..2bf67b1917
--- /dev/null
+++ b/tests/auto/quick/touchmouse/data/twosiblingitems.qml
@@ -0,0 +1,24 @@
+import QtQuick 2.0
+import Qt.test 1.0
+
+Rectangle {
+    id: root
+    width: 320
+    height: 480
+    color: "green"
+
+    EventItem {
+        id: leftItem
+        objectName: "leftItem"
+        width: root.width / 2
+        height: root.height
+    }
+
+    EventItem {
+        objectName: "rightItem"
+        anchors.left: leftItem.right
+        width: root.width / 2
+        height: root.height
+    }
+}
+
diff --git a/tests/auto/quick/touchmouse/tst_touchmouse.cpp b/tests/auto/quick/touchmouse/tst_touchmouse.cpp
index ab1d214369..8c6e3ffc3e 100644
--- a/tests/auto/quick/touchmouse/tst_touchmouse.cpp
+++ b/tests/auto/quick/touchmouse/tst_touchmouse.cpp
@@ -101,10 +101,13 @@ public:
         eventList.append(Event(event->type(), event->pos(), event->globalPos()));
         event->setAccepted(acceptMouse);
     }
+
+    void mouseUngrabEvent()
+    {
+        eventList.append(Event(QEvent::UngrabMouse, QPoint(0,0), QPoint(0,0)));
+    }
+
     bool event(QEvent *event) {
-        if (event->type() == QEvent::UngrabMouse) {
-            eventList.append(Event(event->type(), QPoint(0,0), QPoint(0,0)));
-        }
         return QQuickItem::event(event);
     }
 
@@ -156,6 +159,8 @@ private slots:
 
     void tapOnDismissiveTopMouseAreaClicksBottomOne();
 
+    void touchGrabCausesMouseUngrab();
+
 protected:
     bool eventFilter(QObject *, QEvent *event)
     {
@@ -274,9 +279,10 @@ void tst_TouchMouse::simpleTouchEvent()
     QCOMPARE(eventItem1->eventList.at(3).type, QEvent::MouseMove);
     QTest::touchEvent(window, device).release(0, p1, window);
     QQuickTouchUtils::flush(window);
-    QCOMPARE(eventItem1->eventList.size(), 6);
+    QCOMPARE(eventItem1->eventList.size(), 7);
     QCOMPARE(eventItem1->eventList.at(4).type, QEvent::TouchEnd);
     QCOMPARE(eventItem1->eventList.at(5).type, QEvent::MouseButtonRelease);
+    QCOMPARE(eventItem1->eventList.at(6).type, QEvent::UngrabMouse);
     eventItem1->eventList.clear();
 
     // wait to avoid getting a double click event
@@ -289,16 +295,17 @@ void tst_TouchMouse::simpleTouchEvent()
     p1 = QPoint(20, 20);
     QTest::touchEvent(window, device).press(0, p1, window);
     QQuickTouchUtils::flush(window);
-    QCOMPARE(eventItem1->eventList.size(), 2);
+    QCOMPARE(eventItem1->eventList.size(), 3);
     QCOMPARE(eventItem1->eventList.at(0).type, QEvent::TouchBegin);
     QCOMPARE(eventItem1->eventList.at(1).type, QEvent::MouseButtonPress);
+    QCOMPARE(eventItem1->eventList.at(2).type, QEvent::UngrabMouse);
     p1 += QPoint(10, 0);
     QTest::touchEvent(window, device).move(0, p1, window);
     QQuickTouchUtils::flush(window);
-    QCOMPARE(eventItem1->eventList.size(), 2);
+    QCOMPARE(eventItem1->eventList.size(), 3);
     QTest::touchEvent(window, device).release(0, p1, window);
     QQuickTouchUtils::flush(window);
-    QCOMPARE(eventItem1->eventList.size(), 2);
+    QCOMPARE(eventItem1->eventList.size(), 3);
     eventItem1->eventList.clear();
 
     // wait to avoid getting a double click event
@@ -529,9 +536,10 @@ void tst_TouchMouse::buttonOnFlickable()
     QCOMPARE(eventItem1->eventList.at(1).type, QEvent::MouseButtonPress);
     QTest::touchEvent(window, device).release(0, p1, window);
     QQuickTouchUtils::flush(window);
-    QCOMPARE(eventItem1->eventList.size(), 4);
+    QCOMPARE(eventItem1->eventList.size(), 5);
     QCOMPARE(eventItem1->eventList.at(2).type, QEvent::TouchEnd);
     QCOMPARE(eventItem1->eventList.at(3).type, QEvent::MouseButtonRelease);
+    QCOMPARE(eventItem1->eventList.at(4).type, QEvent::UngrabMouse);
     eventItem1->eventList.clear();
 
     // touch button
@@ -739,18 +747,20 @@ void tst_TouchMouse::buttonOnTouch()
     QQuickTouchUtils::flush(window);
     QTest::touchEvent(window, device).release(0, p1, window);
     QQuickTouchUtils::flush(window);
-    QCOMPARE(eventItem1->eventList.size(), 4);
+    QCOMPARE(eventItem1->eventList.size(), 5);
     QCOMPARE(eventItem1->eventList.at(0).type, QEvent::TouchBegin);
     QCOMPARE(eventItem1->eventList.at(1).type, QEvent::MouseButtonPress);
     QCOMPARE(eventItem1->eventList.at(2).type, QEvent::TouchEnd);
     QCOMPARE(eventItem1->eventList.at(3).type, QEvent::MouseButtonRelease);
+    QCOMPARE(eventItem1->eventList.at(4).type, QEvent::UngrabMouse);
     eventItem1->eventList.clear();
 
     // Normal mouse click
     QTest::mouseClick(window, Qt::LeftButton, 0, p1);
-    QCOMPARE(eventItem1->eventList.size(), 2);
+    QCOMPARE(eventItem1->eventList.size(), 3);
     QCOMPARE(eventItem1->eventList.at(0).type, QEvent::MouseButtonPress);
     QCOMPARE(eventItem1->eventList.at(1).type, QEvent::MouseButtonRelease);
+    QCOMPARE(eventItem1->eventList.at(2).type, QEvent::UngrabMouse);
     eventItem1->eventList.clear();
 
     // Pinch starting on the PinchArea should work
@@ -1169,6 +1179,59 @@ void tst_TouchMouse::tapOnDismissiveTopMouseAreaClicksBottomOne()
     delete window;
 }
 
+/*
+    If an item grabs a touch that is currently being used for mouse pointer emulation,
+    the current mouse grabber should lose the mouse as mouse events will no longer
+    be generated from that touch point.
+ */
+void tst_TouchMouse::touchGrabCausesMouseUngrab()
+{
+    QQuickView *window = createView();
+
+    window->setSource(testFileUrl("twosiblingitems.qml"));
+    window->show();
+    QVERIFY(QTest::qWaitForWindowExposed(window));
+    window->requestActivate();
+    QVERIFY(QTest::qWaitForWindowActive(window));
+    QVERIFY(window->rootObject() != 0);
+
+    EventItem *leftItem = window->rootObject()->findChild<EventItem*>("leftItem");
+    QVERIFY(leftItem);
+
+    EventItem *rightItem = window->rootObject()->findChild<EventItem*>("rightItem");
+    QVERIFY(leftItem);
+
+    // Send a touch to the leftItem. But leftItem accepts only mouse events, thus
+    // a mouse event will be synthesized out of this touch and will get accepted by
+    // leftItem.
+    leftItem->acceptMouse = true;
+    leftItem->setAcceptedMouseButtons(Qt::LeftButton);
+    QPoint p1;
+    p1 = QPoint(leftItem->width() / 2, leftItem->height() / 2);
+    QTest::touchEvent(window, device).press(0, p1, window);
+    QQuickTouchUtils::flush(window);
+    QCOMPARE(leftItem->eventList.size(), 2);
+    QCOMPARE(leftItem->eventList.at(0).type, QEvent::TouchBegin);
+    QCOMPARE(leftItem->eventList.at(1).type, QEvent::MouseButtonPress);
+    QCOMPARE(window->mouseGrabberItem(), leftItem);
+    leftItem->eventList.clear();
+
+    rightItem->acceptTouch = true;
+    {
+        QVector<int> ids;
+        ids.append(0);
+        rightItem->grabTouchPoints(ids);
+    }
+
+    // leftItem should have lost the mouse as the touch point that was being used to emulate it
+    // has been grabbed by another item.
+    QCOMPARE(leftItem->eventList.size(), 1);
+    QCOMPARE(leftItem->eventList.at(0).type, QEvent::UngrabMouse);
+    QCOMPARE(window->mouseGrabberItem(), (QQuickItem*)0);
+
+    delete window;
+}
+
 QTEST_MAIN(tst_TouchMouse)
 
 #include "tst_touchmouse.moc"