QGuiApplication: Prevent double-click recognition across different windows

Two consecutive clicks on different windows should not be recognized as
a double-click event. Add window tracking to ensure double-clicks are
only detected when they occur within the same window.

Changes:
- Add static QWindow tracking for last pressed window
- Add window equality check in double-click detection logic
- Update window tracking after each mouse press event
- Add test auto test case

Fixes: QTBUG-134721
Change-Id: I0ca8460a447ca27b04f3d545176d478c90f6b830
Reviewed-by: Tor Arne Vestbø <[email protected]>

2 files changed, 26 insertions, 1 deletions

diff --git a/src/gui/kernel/qguiapplication.cpp b/src/gui/kernel/qguiapplication.cpp
index 0ed73c18362..c516c56bc78 100644
--- a/src/gui/kernel/qguiapplication.cpp
+++ b/src/gui/kernel/qguiapplication.cpp
@@ -2395,13 +2395,16 @@ void QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::Mo
             mousePressButton = Qt::NoButton;
     } else {
         static unsigned long lastPressTimestamp = 0;
+        static QPointer<QWindow> lastPressWindow = nullptr;
         mouse_buttons = e->buttons;
         if (mousePress) {
             ulong doubleClickInterval = static_cast<ulong>(QGuiApplication::styleHints()->mouseDoubleClickInterval());
             const auto timestampDelta = e->timestamp - lastPressTimestamp;
-            doubleClick = timestampDelta > 0 && timestampDelta < doubleClickInterval && button == mousePressButton;
+            doubleClick = timestampDelta > 0 && timestampDelta < doubleClickInterval
+                          && button == mousePressButton && lastPressWindow == e->window;
             mousePressButton = button;
             lastPressTimestamp = e ->timestamp;
+            lastPressWindow = e->window;
         }
     }
 
diff --git a/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp b/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp
index 71fb2705f52..4c826a1db9e 100644
--- a/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp
+++ b/tests/auto/gui/kernel/qwindow/tst_qwindow.cpp
@@ -1920,6 +1920,28 @@ void tst_QWindow::mouseEventSequence()
     QCOMPARE(window.mouseReleasedCount, 4);
     QCOMPARE(window.mouseDoubleClickedCount, 0);
     QCOMPARE(window.mouseSequenceSignature, QLatin1String("prprprpr"));
+
+    // Test double click across windows
+    InputTestWindow windowNew;
+    windowNew.setGeometry(QRect(m_availableTopLeft + QPoint(80, 80), m_testWindowSize));
+    windowNew.show();
+    QVERIFY(QTest::qWaitForWindowExposed(&windowNew));
+
+    timestamp += doubleClickInterval;
+    windowNew.resetCounters();
+    window.resetCounters();
+
+    simulateMouseClick(&windowNew, timestamp, local, local);
+    simulateMouseClick(&window, timestamp, local, local);
+    QCoreApplication::processEvents();
+    QCOMPARE(windowNew.mousePressedCount, 1);
+    QCOMPARE(windowNew.mouseReleasedCount, 1);
+    QCOMPARE(windowNew.mouseDoubleClickedCount, 0);
+    QCOMPARE(windowNew.mouseSequenceSignature, QLatin1String("pr"));
+    QCOMPARE(window.mousePressedCount, 1);
+    QCOMPARE(window.mouseReleasedCount, 1);
+    QCOMPARE(window.mouseDoubleClickedCount, 0);
+    QCOMPARE(window.mouseSequenceSignature, QLatin1String("pr"));
 }
 
 void tst_QWindow::windowModality()