Synchronize PathView gesture grabbing with other items.

PathView didn't attempt to grab the gesture at the same event as other
items. This prevented PathView from rightfully claiming the gesture
before lower items in the stack. Use the same threshold test for
PathView as used elsewhere.

Task-number: QTBUG-37859
Change-Id: Ic57cb805ac979e41c3e35d86b2e7db781e61d69d
Reviewed-by: Martin Jones <martin.jones@jollamobile.com>

5 files changed, 150 insertions, 9 deletions

diff --git a/src/quick/items/qquickpathview.cpp b/src/quick/items/qquickpathview.cpp
index 335e7611f1..601618d05e 100644
--- a/src/quick/items/qquickpathview.cpp
+++ b/src/quick/items/qquickpathview.cpp
@@ -1599,6 +1599,7 @@ void QQuickPathViewPrivate::handleMousePressEvent(QMouseEvent *event)
         return;
 
     startPoint = pointNear(event->localPos(), &startPc);
+    startPos = event->localPos();
     if (idx == items.count()) {
         qreal distance = qAbs(event->localPos().x() - startPoint.x()) + qAbs(event->localPos().y() - startPoint.y());
         if (distance > dragMargin)
@@ -1621,8 +1622,6 @@ void QQuickPathView::mouseMoveEvent(QMouseEvent *event)
     Q_D(QQuickPathView);
     if (d->interactive) {
         d->handleMouseMoveEvent(event);
-        if (d->stealMouse)
-            setKeepMouseGrab(true);
         event->accept();
     } else {
         QQuickItem::mouseMoveEvent(event);
@@ -1639,9 +1638,17 @@ void QQuickPathViewPrivate::handleMouseMoveEvent(QMouseEvent *event)
     qreal newPc;
     QPointF pathPoint = pointNear(event->localPos(), &newPc);
     if (!stealMouse) {
-        QPointF delta = pathPoint - startPoint;
-        if (qAbs(delta.x()) > qApp->styleHints()->startDragDistance() || qAbs(delta.y()) > qApp->styleHints()->startDragDistance()) {
-            stealMouse = true;
+        QPointF posDelta = event->localPos() - startPos;
+        if (QQuickWindowPrivate::dragOverThreshold(posDelta.y(), Qt::YAxis, event) || QQuickWindowPrivate::dragOverThreshold(posDelta.x(), Qt::XAxis, event)) {
+            // The touch has exceeded the threshold. If the movement along the path is close to the drag threshold
+            // then we'll assume that this gesture targets the PathView. This ensures PathView gesture grabbing
+            // is in sync with other items.
+            QPointF pathDelta = pathPoint - startPoint;
+            if (qAbs(pathDelta.x()) > qApp->styleHints()->startDragDistance() * 0.8
+                    || qAbs(pathDelta.y()) > qApp->styleHints()->startDragDistance() * 0.8) {
+                stealMouse = true;
+                q->setKeepMouseGrab(true);
+            }
         }
     } else {
         moveReason = QQuickPathViewPrivate::Mouse;
diff --git a/src/quick/items/qquickpathview_p_p.h b/src/quick/items/qquickpathview_p_p.h
index e21f3757e6..59a7ac231b 100644
--- a/src/quick/items/qquickpathview_p_p.h
+++ b/src/quick/items/qquickpathview_p_p.h
@@ -135,6 +135,7 @@ public:
     qreal currentItemOffset;
     qreal startPc;
     QPointF startPoint;
+    QPointF startPos;
     qreal offset;
     qreal offsetAdj;
     qreal mappedRange;
diff --git a/tests/auto/quick/qquickpathview/data/flickableDelegate.qml b/tests/auto/quick/qquickpathview/data/flickableDelegate.qml
new file mode 100644
index 0000000000..ed9c34161f
--- /dev/null
+++ b/tests/auto/quick/qquickpathview/data/flickableDelegate.qml
@@ -0,0 +1,78 @@
+/****************************************************************************
+**
+** Copyright (C) 2014 Digia Plc and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/legal
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of Digia Plc and its Subsidiary(-ies) nor the names
+**     of its contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.0
+
+PathView {
+    id: pathView
+    objectName: "pathView"
+    width: 400
+    height: 200
+
+    dragMargin: 400
+    preferredHighlightBegin: 0.3
+    preferredHighlightEnd: 0.3
+
+    model: 3
+    path: Path {
+        startX: -pathView.width/2
+        startY: pathView.height / 2
+        PathLine { x: pathView.width + pathView.width/2; y: pathView.height / 2 }
+    }
+
+    delegate: Flickable {
+        clip: true
+        flickableDirection: Qt.Horizontal
+        width: 200; height: 200
+        contentWidth: 400
+        contentX: 100
+        Rectangle {
+            y: 50
+            x: 50
+            width: 300
+            height: 100
+            color: "purple"
+        }
+Text { text: index }
+        MouseArea {
+            anchors.fill: parent
+        }
+    }
+}
diff --git a/tests/auto/quick/qquickpathview/data/incorrectSteal.qml b/tests/auto/quick/qquickpathview/data/nestedInFlickable.qml
index bcd6923b73..bcd6923b73 100644
--- a/tests/auto/quick/qquickpathview/data/incorrectSteal.qml
+++ b/tests/auto/quick/qquickpathview/data/nestedInFlickable.qml
diff --git a/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp b/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp
index 1960775ad3..0575d8626f 100644
--- a/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp
+++ b/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp
@@ -143,8 +143,9 @@ private slots:
     void indexAt_itemAt();
     void indexAt_itemAt_data();
     void cacheItemCount();
-    void incorrectSteal();
     void changePathDuringRefill();
+    void nestedinFlickable();
+    void flickableDelegate();
 };
 
 class TestObject : public QObject
@@ -2165,11 +2166,11 @@ void tst_QQuickPathView::changePathDuringRefill()
     testCurrentIndexChange(pathView, QStringList() << "delegateA" << "delegateB" << "delegateC");
 }
 
-void tst_QQuickPathView::incorrectSteal()
+void tst_QQuickPathView::nestedinFlickable()
 {
     QScopedPointer<QQuickView> window(createView());
     QQuickViewTestUtil::moveMouseAway(window.data());
-    window->setSource(testFileUrl("incorrectSteal.qml"));
+    window->setSource(testFileUrl("nestedInFlickable.qml"));
     window->show();
     window->requestActivate();
     QVERIFY(QTest::qWaitForWindowActive(window.data()));
@@ -2215,12 +2216,66 @@ void tst_QQuickPathView::incorrectSteal()
     QTRY_COMPARE(moveEndedSpy.count(), 1);
     QCOMPARE(moveStartedSpy.count(), 1);
     // Flickable should not handle this
-    QEXPECT_FAIL("", "QTBUG-37859", Abort);
     QCOMPARE(fflickingSpy.count(), 0);
     QCOMPARE(fflickStartedSpy.count(), 0);
     QCOMPARE(fflickEndedSpy.count(), 0);
 }
 
+void tst_QQuickPathView::flickableDelegate()
+{
+    QScopedPointer<QQuickView> window(createView());
+    QQuickViewTestUtil::moveMouseAway(window.data());
+    window->setSource(testFileUrl("flickableDelegate.qml"));
+    window->show();
+    window->requestActivate();
+    QVERIFY(QTest::qWaitForWindowActive(window.data()));
+    QCOMPARE(window.data(), qGuiApp->focusWindow());
+
+    QQuickPathView *pathview = qobject_cast<QQuickPathView*>(window->rootObject());
+    QVERIFY(pathview != 0);
+
+    QQuickFlickable *flickable = qobject_cast<QQuickFlickable*>(pathview->currentItem());
+    QVERIFY(flickable != 0);
+
+    QSignalSpy movingSpy(pathview, SIGNAL(movingChanged()));
+    QSignalSpy moveStartedSpy(pathview, SIGNAL(movementStarted()));
+    QSignalSpy moveEndedSpy(pathview, SIGNAL(movementEnded()));
+
+    QSignalSpy fflickingSpy(flickable, SIGNAL(flickingChanged()));
+    QSignalSpy fflickStartedSpy(flickable, SIGNAL(flickStarted()));
+    QSignalSpy fflickEndedSpy(flickable, SIGNAL(flickEnded()));
+
+    int waitInterval = 5;
+
+    QTest::mousePress(window.data(), Qt::LeftButton, 0, QPoint(23,100));
+
+    QTest::mouseMove(window.data(), QPoint(25,100), waitInterval);
+    QTest::mouseMove(window.data(), QPoint(26,100), waitInterval);
+    QTest::mouseMove(window.data(), QPoint(28,100), waitInterval);
+    QTest::mouseMove(window.data(), QPoint(31,100), waitInterval);
+    QTest::mouseMove(window.data(), QPoint(39,100), waitInterval);
+
+    // first move beyond threshold does not trigger drag
+    QVERIFY(!flickable->isMoving());
+    QVERIFY(!flickable->isDragging());
+    QCOMPARE(movingSpy.count(), 0);
+    QCOMPARE(moveStartedSpy.count(), 0);
+    QCOMPARE(moveEndedSpy.count(), 0);
+    QCOMPARE(fflickingSpy.count(), 0);
+    QCOMPARE(fflickStartedSpy.count(), 0);
+    QCOMPARE(fflickEndedSpy.count(), 0);
+
+    // no further moves after the initial move beyond threshold
+    QTest::mouseRelease(window.data(), Qt::LeftButton, 0, QPoint(53,100));
+    QTRY_COMPARE(fflickingSpy.count(), 2);
+    QTRY_COMPARE(fflickStartedSpy.count(), 1);
+    QCOMPARE(fflickEndedSpy.count(), 1);
+    // PathView should not handle this
+    QTRY_COMPARE(movingSpy.count(), 0);
+    QTRY_COMPARE(moveEndedSpy.count(), 0);
+    QCOMPARE(moveStartedSpy.count(), 0);
+}
+
 QTEST_MAIN(tst_QQuickPathView)
 
 #include "tst_qquickpathview.moc"