Improve the ordering of Flickable dragging and moving property updates.

Move the contentItem after the dragging and moving properties have been
updated so they return the correct values from the onContentYChanged
and onContentXChanged handlers.

Task-number: QTBUG-30032
Change-Id: I15716dc8eee4d9836f96362a8b49f1d0c404b0c2
Reviewed-by: Alan Alpert <aalpert@blackberry.com>

3 files changed, 37 insertions, 4 deletions

diff --git a/src/quick/items/qquickflickable.cpp b/src/quick/items/qquickflickable.cpp
index 3482db0dfe..9346c79847 100644
--- a/src/quick/items/qquickflickable.cpp
+++ b/src/quick/items/qquickflickable.cpp
@@ -1014,6 +1014,12 @@ void QQuickFlickablePrivate::handleMouseMoveEvent(QMouseEvent *event)
     bool prevHMoved = hMoved;
     bool prevVMoved = vMoved;
 
+    bool moveY = false;
+    bool moveX = false;
+
+    qreal newY = 0;
+    qreal newX = 0;
+
     qint64 elapsedSincePress = computeCurrentTime(event) - lastPressTime;
     if (q->yflick()) {
         qreal dy = event->localPos().y() - pressPos.y();
@@ -1021,7 +1027,7 @@ void QQuickFlickablePrivate::handleMouseMoveEvent(QMouseEvent *event)
         if (vData.dragStartOffset == 0)
             vData.dragStartOffset = dy;
         if (overThreshold || elapsedSincePress > 200) {
-            qreal newY = dy + vData.pressPos - vData.dragStartOffset;
+            newY = dy + vData.pressPos - vData.dragStartOffset;
             // Recalculate bounds in case margins have changed, but use the content
             // size estimate taken at the start of the drag in case the drag causes
             // the estimate to be altered
@@ -1041,8 +1047,8 @@ void QQuickFlickablePrivate::handleMouseMoveEvent(QMouseEvent *event)
             }
             if (!rejectY && stealMouse && dy != 0.0) {
                 clearTimeline();
-                vData.move.setValue(newY);
                 vMoved = true;
+                moveY = true;
             }
             if (!rejectY && overThreshold)
                 stealY = true;
@@ -1055,7 +1061,7 @@ void QQuickFlickablePrivate::handleMouseMoveEvent(QMouseEvent *event)
         if (hData.dragStartOffset == 0)
             hData.dragStartOffset = dx;
         if (overThreshold || elapsedSincePress > 200) {
-            qreal newX = dx + hData.pressPos - hData.dragStartOffset;
+            newX = dx + hData.pressPos - hData.dragStartOffset;
             const qreal minX = hData.dragMinBound + hData.startMargin;
             const qreal maxX = hData.dragMaxBound - hData.endMargin;
             if (newX > minX)
@@ -1073,8 +1079,8 @@ void QQuickFlickablePrivate::handleMouseMoveEvent(QMouseEvent *event)
 
             if (!rejectX && stealMouse && dx != 0.0) {
                 clearTimeline();
-                hData.move.setValue(newX);
                 hMoved = true;
+                moveX = true;
             }
 
             if (!rejectX && overThreshold)
@@ -1102,6 +1108,11 @@ void QQuickFlickablePrivate::handleMouseMoveEvent(QMouseEvent *event)
         q->movementStarting();
     }
 
+    if (moveY)
+        vData.move.setValue(newY);
+    if (moveX)
+        hData.move.setValue(newX);
+
     qint64 currentTimestamp = computeCurrentTime(event);
     qreal elapsed = qreal(currentTimestamp - (lastPos.isNull() ? lastPressTime : lastPosTime)) / 1000.;
     if (elapsed <= 0)
diff --git a/tests/auto/quick/qquickflickable/data/flickable03.qml b/tests/auto/quick/qquickflickable/data/flickable03.qml
index a3e9d6fd59..1549034576 100644
--- a/tests/auto/quick/qquickflickable/data/flickable03.qml
+++ b/tests/auto/quick/qquickflickable/data/flickable03.qml
@@ -1,9 +1,23 @@
 import QtQuick 2.0
 
 Flickable {
+    property bool movingInContentX: true
+    property bool movingInContentY: true
+    property bool draggingInContentX: true
+    property bool draggingInContentY: true
+
     width: 100; height: 400
     contentWidth: column.width; contentHeight: column.height
 
+    onContentXChanged: {
+        movingInContentX = movingInContentX && movingHorizontally
+        draggingInContentX = draggingInContentX && draggingHorizontally
+    }
+    onContentYChanged: {
+        movingInContentY = movingInContentY && movingVertically
+        draggingInContentY = draggingInContentY && draggingVertically
+    }
+
     Column {
         id: column
         Repeater {
diff --git a/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp b/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp
index 57c4c12264..c4f871fc11 100644
--- a/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp
+++ b/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp
@@ -647,6 +647,9 @@ void tst_qquickflickable::movingAndFlicking()
     QVERIFY(flickable->isFlicking());
     QCOMPARE(flickable->isFlickingHorizontally(), horizontalEnabled);
     QCOMPARE(flickable->isFlickingVertically(), verticalEnabled);
+    // contentX/contentY are either unchanged, or moving is true when the value changed.
+    QCOMPARE(flickable->property("movingInContentX").value<bool>(), true);
+    QCOMPARE(flickable->property("movingInContentY").value<bool>(), true);
 
     QCOMPARE(moveSpy.count(), 1);
     QCOMPARE(vMoveSpy.count(), verticalEnabled ? 1 : 0);
@@ -810,6 +813,11 @@ void tst_qquickflickable::movingAndDragging()
     QVERIFY(flickable->isDragging());
     QCOMPARE(flickable->isDraggingHorizontally(), horizontalEnabled);
     QCOMPARE(flickable->isDraggingVertically(), verticalEnabled);
+    // contentX/contentY are either unchanged, or moving and dragging are true when the value changes.
+    QCOMPARE(flickable->property("movingInContentX").value<bool>(), true);
+    QCOMPARE(flickable->property("movingInContentY").value<bool>(), true);
+    QCOMPARE(flickable->property("draggingInContentX").value<bool>(), true);
+    QCOMPARE(flickable->property("draggingInContentY").value<bool>(), true);
 
     QCOMPARE(moveSpy.count(), 1);
     QCOMPARE(vMoveSpy.count(), verticalEnabled ? 1 : 0);