From c6f88a807c9872f81000dc01de94145022bc76c5 Mon Sep 17 00:00:00 2001
From: Richard Moe Gustavsen <richard.gustavsen@qt.io>
Date: Tue, 17 Oct 2023 14:51:21 +0200
Subject: [PATCH] QQuickFlickable: release drag if receiving
 QEvent::TouchCancel
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If a TouchCancel event is sent to a Flickable, it should abort
any current dragging operation done by the user. This patch will
ensure that we do so.

Fixes: QTBUG-117160
Change-Id: Iff332e597a0502396c2fd0e4988f01ab2119314d
Reviewed-by: Jan Arve Sæther <jan-arve.saether@qt.io>
Reviewed-by: Seokha Ko <seokha.ko@qt.io>
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>
(cherry picked from commit 5093e4c24347a2044e23ba057c0dfdc64df5019d)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
(cherry picked from commit 3544aae7286902d22b5bdd3a0d5ee89578ce8814)
---
 src/quick/items/qquickflickable.cpp           |  9 ++++++
 .../qquickflickable/tst_qquickflickable.cpp   | 29 +++++++++++++++++++
 2 files changed, 38 insertions(+)

diff --git a/src/quick/items/qquickflickable.cpp b/src/quick/items/qquickflickable.cpp
index 7eac4fe471..cda8e62587 100644
--- a/src/quick/items/qquickflickable.cpp
+++ b/src/quick/items/qquickflickable.cpp
@@ -1546,6 +1546,15 @@ void QQuickFlickable::mouseReleaseEvent(QMouseEvent *event)
 void QQuickFlickable::touchEvent(QTouchEvent *event)
 {
     Q_D(QQuickFlickable);
+
+    if (event->type() == QEvent::TouchCancel) {
+        if (d->interactive && d->wantsPointerEvent(event))
+            d->cancelInteraction();
+        else
+            QQuickItem::touchEvent(event);
+        return;
+    }
+
     bool unhandled = false;
     const auto &firstPoint = event->points().first();
     switch (firstPoint.state()) {
diff --git a/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp b/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp
index 7c0bdcadea..37810c967d 100644
--- a/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp
+++ b/tests/auto/quick/qquickflickable/tst_qquickflickable.cpp
@@ -224,6 +224,7 @@ private slots:
     void setContentPositionWhileDragging();
     void coalescedMove();
     void onlyOneMove();
+    void touchCancel();
 
 private:
     void flickWithTouch(QQuickWindow *window, const QPoint &from, const QPoint &to);
@@ -3236,6 +3237,34 @@ void tst_qquickflickable::onlyOneMove()
     QCOMPARE(flickEndedSpy.size(), 1);
 }
 
+void tst_qquickflickable::touchCancel()
+{
+    QQuickView window;
+    QVERIFY(QQuickTest::showView(window, testFileUrl("flickable03.qml")));
+    QQuickViewTestUtils::centerOnScreen(&window);
+    QVERIFY(window.isVisible());
+
+    QQuickFlickable *flickable = qobject_cast<QQuickFlickable*>(window.rootObject());
+    QVERIFY(flickable != nullptr);
+
+    QSignalSpy movementStartedSpy(flickable, SIGNAL(movementStarted()));
+    QSignalSpy movementEndedSpy(flickable, SIGNAL(movementEnded()));
+
+    int touchPosY = 10;
+    QTest::touchEvent(&window, touchDevice).press(0, {10, touchPosY}).commit();
+    QQuickTouchUtils::flush(&window);
+
+    for (int i = 0; i < 3; ++i) {
+        touchPosY += qApp->styleHints()->startDragDistance();
+        QTest::touchEvent(&window, touchDevice).move(0, {10, touchPosY}).commit();
+        QQuickTouchUtils::flush(&window);
+    }
+
+    QTRY_COMPARE(movementStartedSpy.size(), 1);
+    QWindowSystemInterface::handleTouchCancelEvent(nullptr, touchDevice);
+    QTRY_COMPARE(movementEndedSpy.size(), 1);
+}
+
 QTEST_MAIN(tst_qquickflickable)
 
 #include "tst_qquickflickable.moc"