Windows QPA: Move the touch types API from platformheaders into QtGui

Change TouchWindowTouchType(s) to be (global) property of
QGuiApplication's native Windows interface since it does not make
sense to set it per window.

It appears the previous code setting the types per Window has never
worked since registerTouchWindow() bailed out due to the checks for
the flags TouchRegistered and IsTouchWindow() (setting in
HCBT_CREATEWND). In addition, registering windows for touch after
plugging in a device would not observe the setting.

Move the checks around to make this work.

Task-number: QTBUG-41433
Task-number: QTBUG-48849
Task-number: QTBUG-83252
Change-Id: I4306fdf13208f6eef22655875f3bd1769270e617
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

1 files changed, 36 insertions, 18 deletions

diff --git a/src/plugins/platforms/windows/qwindowswindow.cpp b/src/plugins/platforms/windows/qwindowswindow.cpp
index 8df4bb3428..cd234e22b7 100644
--- a/src/plugins/platforms/windows/qwindowswindow.cpp
+++ b/src/plugins/platforms/windows/qwindowswindow.cpp
@@ -1128,6 +1128,20 @@ QMargins QWindowsBaseWindow::frameMargins_sys() const
     return QWindowsGeometryHint::frame(handle(), style(), exStyle());
 }
 
+std::optional<QWindowsBaseWindow::TouchWindowTouchTypes>
+    QWindowsBaseWindow::touchWindowTouchTypes_sys() const
+{
+    ULONG touchFlags = 0;
+    if (IsTouchWindow(handle(), &touchFlags) == FALSE)
+        return {};
+    TouchWindowTouchTypes result;
+    if ((touchFlags & TWF_FINETOUCH) != 0)
+        result.setFlag(TouchWindowTouchType::FineTouch);
+    if ((touchFlags & TWF_WANTPALM) != 0)
+        result.setFlag(TouchWindowTouchType::WantPalmTouch);
+    return result;
+}
+
 void QWindowsBaseWindow::hide_sys() // Normal hide, do not activate other windows.
 {
     SetWindowPos(handle(), nullptr , 0, 0, 0, 0,
@@ -1345,7 +1359,11 @@ QWindowsWindow::QWindowsWindow(QWindow *aWindow, const QWindowsWindowData &data)
 #endif
     updateDropSite(window()->isTopLevel());
 
-    registerTouchWindow();
+    // Register touch unless if the flags are already set by a hook
+    // such as HCBT_CREATEWND
+    if (!touchWindowTouchTypes_sys().has_value())
+        registerTouchWindow();
+
     const qreal opacity = qt_window_private(aWindow)->opacity;
     if (!qFuzzyCompare(opacity, qreal(1.0)))
         setOpacity(opacity);
@@ -3040,28 +3058,28 @@ void QWindowsWindow::invalidateSurface()
 #endif // QT_NO_OPENGL
 }
 
-void QWindowsWindow::setTouchWindowTouchTypeStatic(QWindow *window, QWindowsWindowFunctions::TouchWindowTouchTypes touchTypes)
+void QWindowsWindow::registerTouchWindow()
 {
-    if (!window->handle())
+    if ((QWindowsContext::instance()->systemInfo() & QWindowsContext::SI_SupportsTouch) == 0)
         return;
-    static_cast<QWindowsWindow *>(window->handle())->registerTouchWindow(touchTypes);
-}
 
-void QWindowsWindow::registerTouchWindow(QWindowsWindowFunctions::TouchWindowTouchTypes touchTypes)
-{
-    if ((QWindowsContext::instance()->systemInfo() & QWindowsContext::SI_SupportsTouch)
-        && !testFlag(TouchRegistered)) {
-        ULONG touchFlags = 0;
-        const bool ret = IsTouchWindow(m_data.hwnd, &touchFlags);
-        // Return if it is not a touch window or the flags are already set by a hook
-        // such as HCBT_CREATEWND
-        if (ret || touchFlags != 0)
+    // Initially register or re-register to change the flags
+    const auto touchTypes = QWindowsIntegration::instance()->touchWindowTouchType();
+    if (testFlag(TouchRegistered)) {
+        const auto currentTouchTypes = touchWindowTouchTypes_sys();
+        if (currentTouchTypes.has_value() && currentTouchTypes.value() == touchTypes)
             return;
-        if (RegisterTouchWindow(m_data.hwnd, ULONG(touchTypes)))
-            setFlag(TouchRegistered);
-        else
-            qErrnoWarning("RegisterTouchWindow() failed for window '%s'.", qPrintable(window()->objectName()));
     }
+
+    ULONG touchFlags = 0;
+    if (touchTypes.testFlag(TouchWindowTouchType::FineTouch))
+        touchFlags |= TWF_FINETOUCH;
+    if (touchTypes.testFlag(TouchWindowTouchType::WantPalmTouch))
+        touchFlags |= TWF_WANTPALM;
+    if (RegisterTouchWindow(m_data.hwnd, touchFlags))
+        setFlag(TouchRegistered);
+    else
+        qErrnoWarning("RegisterTouchWindow() failed for window '%s'.", qPrintable(window()->objectName()));
 }
 
 void QWindowsWindow::aboutToMakeCurrent()