Windows QPA: Implement QPlatformWindow::startSystemMove()

Task-number: QTBUG-58044
Change-Id: I15639d505683159b4cc31d762cb0bebbfc57e594
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

2 files changed, 11 insertions, 0 deletions

diff --git a/src/plugins/platforms/windows/qwindowswindow.cpp b/src/plugins/platforms/windows/qwindowswindow.cpp
index 854c19ccf8..ada124b5af 100644
--- a/src/plugins/platforms/windows/qwindowswindow.cpp
+++ b/src/plugins/platforms/windows/qwindowswindow.cpp
@@ -2277,6 +2277,16 @@ bool QWindowsWindow::startSystemResize(const QPoint &, Qt::Corner corner)
     return true;
 }
 
+bool QWindowsWindow::startSystemMove(const QPoint &)
+{
+    if (!GetSystemMenu(m_data.hwnd, FALSE))
+        return false;
+
+    ReleaseCapture();
+    PostMessage(m_data.hwnd, WM_SYSCOMMAND, 0xF012 /*SC_DRAGMOVE*/, 0);
+    return true;
+}
+
 void QWindowsWindow::setFrameStrutEventsEnabled(bool enabled)
 {
     if (enabled) {
diff --git a/src/plugins/platforms/windows/qwindowswindow.h b/src/plugins/platforms/windows/qwindowswindow.h
index 414d4a92f8..3732255738 100644
--- a/src/plugins/platforms/windows/qwindowswindow.h
+++ b/src/plugins/platforms/windows/qwindowswindow.h
@@ -269,6 +269,7 @@ public:
     inline bool hasMouseCapture() const { return GetCapture() == m_data.hwnd; }
 
     bool startSystemResize(const QPoint &pos, Qt::Corner corner) override;
+    bool startSystemMove(const QPoint &pos) override;
 
     void setFrameStrutEventsEnabled(bool enabled) override;
     bool frameStrutEventsEnabled() const override { return testFlag(FrameStrutEventsEnabled); }