PathView: grab mouse on press if already moving

A side effect of 8fd398c9d2f5f54e446e0b402bc63a2edb50da6f is that it
became possible for the highlight to stop between items, rather than
snapping to a specific item, if the user taps, clicks or drags an
additional time while the movement is ongoing.  That was because it
didn't get a mouse grab, so it missed the release event.
QQuickPathViewPrivate::handleMouseReleaseEvent() needs to take care of
the snapping behavior after the user stops dragging.  This only affects
behavior in the case that the PathView is already moving and the mouse
is pressed again: we assume the user wants to alter the PathView's
velocity, not interact with any delegate inside or with any parent item.

Task-number: QTBUG-77173
Task-number: QTBUG-59620
Change-Id: I7b2f69a6ef8d8022d7c917a5bf9e8fb40c8848db
Reviewed-by: Mitch Curtis <mitch.curtis@qt.io>
(cherry picked from commit e2df4233a77ce8a37d2c8ef26b7b42fc0d33a24b)

2 files changed, 128 insertions, 0 deletions

diff --git a/tests/auto/quick/qquickpathview/data/nestedmousearea2.qml b/tests/auto/quick/qquickpathview/data/nestedmousearea2.qml
new file mode 100644
index 0000000000..ff11002552
--- /dev/null
+++ b/tests/auto/quick/qquickpathview/data/nestedmousearea2.qml
@@ -0,0 +1,101 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** BSD License Usage
+** Alternatively, 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 The Qt Company Ltd 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: view
+    width: 400; height: 240
+    highlight: Rectangle { width: 80; height: 80; color: "lightsteelblue" }
+    preferredHighlightBegin: 0.5
+    preferredHighlightEnd: 0.5
+    model: ListModel {
+        id: appModel
+        ListElement { name: "Music" }
+        ListElement { name: "Movies" }
+        ListElement { name: "Camera" }
+        ListElement { name: "Calendar" }
+        ListElement { name: "Messaging" }
+        ListElement { name: "Todo List" }
+        ListElement { name: "Contacts" }
+    }
+    delegate: Rectangle {
+        width: 100; height: 100
+        scale: PathView.iconScale
+        border.color: "lightgrey"
+        color: "transparent"
+        Text {
+            anchors { horizontalCenter: parent.horizontalCenter }
+            text: name
+            smooth: true
+            color: ma.pressed ? "red" : "black"
+        }
+
+        MouseArea {
+            id: ma
+            anchors.fill: parent
+            onClicked: view.currentIndex = index
+        }
+    }
+    path: Path {
+        startX: 10
+        startY: 50
+        PathAttribute { name: "iconScale"; value: 0.5 }
+        PathQuad { x: 200; y: 150; controlX: 50; controlY: 200 }
+        PathAttribute { name: "iconScale"; value: 1.0 }
+        PathQuad { x: 390; y: 50; controlX: 350; controlY: 200 }
+        PathAttribute { name: "iconScale"; value: 0.5 }
+    }
+    Text {
+        anchors.horizontalCenter: parent.horizontalCenter
+        y: 20
+        text: view.currentIndex + " @ " + offset.toFixed(2)
+    }
+}
diff --git a/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp b/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp
index 355800359c..eda48676bc 100644
--- a/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp
+++ b/tests/auto/quick/qquickpathview/tst_qquickpathview.cpp
@@ -119,6 +119,7 @@ private slots:
     void undefinedPath();
     void mouseDrag();
     void nestedMouseAreaDrag();
+    void flickNClick();
     void treeModel();
     void changePreferredHighlight();
     void missingPercent();
@@ -1600,6 +1601,32 @@ void tst_QQuickPathView::nestedMouseAreaDrag()
     QVERIFY(pathview->isMoving());
 }
 
+void tst_QQuickPathView::flickNClick() // QTBUG-77173
+{
+    QScopedPointer<QQuickView> window(createView());
+    QQuickViewTestUtil::moveMouseAway(window.data());
+    window->setSource(testFileUrl("nestedmousearea2.qml"));
+    window->show();
+    window->requestActivate();
+    QVERIFY(QTest::qWaitForWindowActive(window.data()));
+    QCOMPARE(window.data(), qGuiApp->focusWindow());
+
+    QQuickPathView *pathview = qobject_cast<QQuickPathView*>(window->rootObject());
+    QVERIFY(pathview != nullptr);
+
+    for (int duration = 100; duration > 0; duration -= 20) {
+        // Dragging the child mouse area should animate the PathView (MA has no drag target)
+        flick(window.data(), QPoint(200,200), QPoint(400,200), duration);
+        QVERIFY(pathview->isMoving());
+
+        // Now while it's still moving, click it.
+        // The PathView should stop at a position such that offset is a whole number.
+        QTest::mouseClick(window.data(), Qt::LeftButton, Qt::NoModifier, QPoint(200, 200));
+        QTRY_VERIFY(!pathview->isMoving());
+        QVERIFY(qFuzzyIsNull(pathview->offset() - int(pathview->offset())));
+    }
+}
+
 void tst_QQuickPathView::treeModel()
 {
     QScopedPointer<QQuickView> window(createView());