Do not rely on synthesized MouseReleseEvent when tracking mouse point

A map pan is based on synthesized events due to the fact that
rest of qt (qtcontrols , mouse area etc) depend on it in case of touch
handling. However when there are two touch points on the screen
pinch handling is activated. After accepting the touch event,
mouse synthesized events are no longer generated for the first touch
point, what's more as a result we might not get even
mouseUngrabEvent nor mouseReleaseEvent. This breaks internal
tracking of mouse position. This workaround resets mouse tracking point
in case of getting touchUngrabEvent.

Remove dummy extra MouseArea from places example.

TODO: fix broken mouse area state in pinch unit tests

Task-number:  QTBUG-46388
Change-Id: I5588fbd4dbf0c5d25c44f994292c1aae7b3d70d4
Reviewed-by: Alex Blasche <alexander.blasche@theqtcompany.com>

4 files changed, 23 insertions, 13 deletions

diff --git a/examples/location/places/items/MapComponent.qml b/examples/location/places/items/MapComponent.qml
index ccf1415d..de4e04a7 100644
--- a/examples/location/places/items/MapComponent.qml
+++ b/examples/location/places/items/MapComponent.qml
@@ -211,9 +211,4 @@ Map {
             map.zoomLevel = value
         }
     }
-
-    MouseArea {
-        //workaround for QTBUG-46388
-        anchors.fill: parent
-    }
 }
diff --git a/src/imports/location/qdeclarativegeomap.cpp b/src/imports/location/qdeclarativegeomap.cpp
index ccff4fd1..cf492977 100644
--- a/src/imports/location/qdeclarativegeomap.cpp
+++ b/src/imports/location/qdeclarativegeomap.cpp
@@ -942,9 +942,10 @@ void QDeclarativeGeoMap::touchEvent(QTouchEvent *event)
              event->type() == QEvent::TouchCancel) {
             ungrabTouchPoints();
         }
+    } else {
+        //ignore event so sythesized event is generated;
+        QQuickItem::touchEvent(event);
     }
-    //this will always ignore event so sythesized event is generated;
-    QQuickItem::touchEvent(event);
 }
 
 /*!
diff --git a/src/imports/location/qquickgeomapgesturearea.cpp b/src/imports/location/qquickgeomapgesturearea.cpp
index c3536e11..8c4eadda 100644
--- a/src/imports/location/qquickgeomapgesturearea.cpp
+++ b/src/imports/location/qquickgeomapgesturearea.cpp
@@ -620,8 +620,12 @@ void QQuickGeoMapGestureArea::handleMouseMoveEvent(QMouseEvent *event)
 */
 void QQuickGeoMapGestureArea::handleMouseReleaseEvent(QMouseEvent *event)
 {
-    m_mousePoint.reset(createTouchPointFromMouseEvent(event, Qt::TouchPointReleased));
-    if (m_touchPoints.isEmpty()) update();
+    if (!m_mousePoint.isNull()) {
+        //this looks super ugly , however is required in case we do not get synthesized MouseReleaseEvent
+        //and we reset the point already in handleTouchUngrabEvent
+        m_mousePoint.reset(createTouchPointFromMouseEvent(event, Qt::TouchPointReleased));
+        if (m_touchPoints.isEmpty()) update();
+    }
     event->accept();
 }
 
@@ -630,9 +634,13 @@ void QQuickGeoMapGestureArea::handleMouseReleaseEvent(QMouseEvent *event)
 */
 void QQuickGeoMapGestureArea::handleMouseUngrabEvent()
 {
-    m_mousePoint.reset();
-    if (m_touchPoints.isEmpty())
+
+    if (m_touchPoints.isEmpty() && !m_mousePoint.isNull()) {
+        m_mousePoint.reset();
         update();
+    } else {
+        m_mousePoint.reset();
+    }
 }
 
 /*!
@@ -640,8 +648,11 @@ void QQuickGeoMapGestureArea::handleMouseUngrabEvent()
 */
 void QQuickGeoMapGestureArea::handleTouchUngrabEvent()
 {
-    m_touchPoints.clear();
-    update();
+        m_touchPoints.clear();
+        //this is needed since in some cases mouse release is not delivered
+        //(second touch point brakes mouse synthesized events)
+        m_mousePoint.reset();
+        update();
 }
 
 /*!
@@ -654,6 +665,8 @@ void QQuickGeoMapGestureArea::handleTouchEvent(QTouchEvent *event)
         m_touchPoints << event->touchPoints().at(i);
     if (event->touchPoints().count() >= 2)
         event->accept();
+    else
+        event->ignore();
     update();
 }
 
diff --git a/tests/auto/declarative_ui/tst_map_pinch.qml b/tests/auto/declarative_ui/tst_map_pinch.qml
index bdf88e29..f4e57faa 100644
--- a/tests/auto/declarative_ui/tst_map_pinch.qml
+++ b/tests/auto/declarative_ui/tst_map_pinch.qml
@@ -118,6 +118,7 @@ Item {
             map.center = coordinate
             map.minimumZoomLevel = 0
             map.maximumZoomLevel = 20
+            mouseRelease(mouseAreaTop,0,0) //Fixme: mouse area state gets broken across the tests
             mouseAreaBottom.visible = false
             mouseAreaTop.visible = false
             pinchGenerator.clear()