Make QWindow's windowState a QFlags of the WindowState

This reflects QWidget API, and restores some behavior from Qt4.
Some WM can have several state at the same time. On Plasma for example,
when a window is both maximized and minimized, the "maximized" checkbox
is checked from the taskbar entry.

The API of QPlatformWindow was changed to take a QFlag and the platform
plugins were adapted.

 - On XCB: Always send the full state to the WM. And read the full state.

 - On Windows: The code was originally written with '&' in Qt4, and was changed
   to == when porting. Some adaptation had to be made so the states would be
   preserved.

 - On macOS: Only a single state can be set and is reported back for now,
   with the possibly to expand this in the future.

 - Other platforms: Just do as before with the effective state.

Task-number: QTBUG-57882
Task-number: QTBUG-52616
Task-number: QTBUG-52555
Change-Id: I7a1f7cac64236bbd4c591f796374315639233dad
Reviewed-by: Gunnar Sletta <gunnar@crimson.no>
Reviewed-by: Robin Burchell <robin.burchell@crimson.no>

1 files changed, 12 insertions, 9 deletions

diff --git a/src/plugins/platforms/winrt/qwinrtwindow.cpp b/src/plugins/platforms/winrt/qwinrtwindow.cpp
index c40a1b8c45..cbf0ba36c9 100644
--- a/src/plugins/platforms/winrt/qwinrtwindow.cpp
+++ b/src/plugins/platforms/winrt/qwinrtwindow.cpp
@@ -91,7 +91,7 @@ public:
 
     QSurfaceFormat surfaceFormat;
     QString windowTitle;
-    Qt::WindowState state;
+    Qt::WindowStates state;
     EGLDisplay display;
     EGLSurface surface;
 
@@ -158,7 +158,7 @@ QWinRTWindow::QWinRTWindow(QWindow *window)
     Q_ASSERT_SUCCEEDED(hr);
 
     setWindowFlags(window->flags());
-    setWindowState(window->windowState());
+    setWindowState(window->windowStates());
     setWindowTitle(window->title());
 
     setGeometry(window->geometry());
@@ -323,7 +323,7 @@ qreal QWinRTWindow::devicePixelRatio() const
     return screen()->devicePixelRatio();
 }
 
-void QWinRTWindow::setWindowState(Qt::WindowState state)
+void QWinRTWindow::setWindowState(Qt::WindowStates state)
 {
     Q_D(QWinRTWindow);
     qCDebug(lcQpaWindows) << __FUNCTION__ << this << state;
@@ -331,7 +331,13 @@ void QWinRTWindow::setWindowState(Qt::WindowState state)
     if (d->state == state)
         return;
 
-    if (state == Qt::WindowFullScreen) {
+    if (state & Qt::WindowMinimized) {
+        setUIElementVisibility(d->uiElement.Get(), false);
+        d->state = state;
+        return;
+    }
+
+    if (state & Qt::WindowFullScreen) {
         HRESULT hr;
         boolean success;
         hr = QEventDispatcherWinRT::runOnXamlThread([&hr, &success]() {
@@ -356,7 +362,7 @@ void QWinRTWindow::setWindowState(Qt::WindowState state)
         return;
     }
 
-    if (d->state == Qt::WindowFullScreen) {
+    if (d->state & Qt::WindowFullScreen) {
         HRESULT hr;
         hr = QEventDispatcherWinRT::runOnXamlThread([&hr]() {
             ComPtr<IApplicationViewStatics2> applicationViewStatics;
@@ -378,10 +384,7 @@ void QWinRTWindow::setWindowState(Qt::WindowState state)
         }
     }
 
-    if (state == Qt::WindowMinimized)
-        setUIElementVisibility(d->uiElement.Get(), false);
-
-    if (d->state == Qt::WindowMinimized || state == Qt::WindowNoState || state == Qt::WindowActive)
+    if (d->state & Qt::WindowMinimized || state == Qt::WindowNoState || state == Qt::WindowActive)
         setUIElementVisibility(d->uiElement.Get(), true);
 
     d->state = state;