xcb: unset states and set new ones as need

Should not unset all the old state and set the new ones.
Only unset the state that needs to be unset.

If states changes from maximized to minimized, there is no need to
unset the maximized state and set the maximized states again.
(minimized and maximized can exist simultaneously :)

This amends f61b140482d9578c07410a5979379e44e05352e5 .

Pick-to: 6.6 6.5 6.2
Change-Id: Ic93122b92fafcdba973b885e299b282408da7a1c
Reviewed-by: Liang Qi <liang.qi@qt.io>

1 files changed, 8 insertions, 10 deletions

diff --git a/src/plugins/platforms/xcb/qxcbwindow.cpp b/src/plugins/platforms/xcb/qxcbwindow.cpp
index 19e0256099..3fcc605bfe 100644
--- a/src/plugins/platforms/xcb/qxcbwindow.cpp
+++ b/src/plugins/platforms/xcb/qxcbwindow.cpp
@@ -1129,18 +1129,21 @@ void QXcbWindow::setWindowState(Qt::WindowStates state)
     if (state == m_windowState)
         return;
 
+    Qt::WindowStates unsetState = m_windowState & ~state;
+    Qt::WindowStates newState =  state & ~m_windowState;
+
     // unset old state
-    if (m_windowState & Qt::WindowMinimized)
+    if (unsetState & Qt::WindowMinimized)
         xcb_map_window(xcb_connection(), m_window);
-    if (m_windowState & Qt::WindowMaximized)
+    if (unsetState & Qt::WindowMaximized)
         setNetWmState(false,
                       atom(QXcbAtom::Atom_NET_WM_STATE_MAXIMIZED_HORZ),
                       atom(QXcbAtom::Atom_NET_WM_STATE_MAXIMIZED_VERT));
-    if (m_windowState & Qt::WindowFullScreen)
+    if (unsetState & Qt::WindowFullScreen)
         setNetWmState(false, atom(QXcbAtom::Atom_NET_WM_STATE_FULLSCREEN));
 
     // set new state
-    if (state & Qt::WindowMinimized) {
+    if (newState & Qt::WindowMinimized) {
         {
             xcb_client_message_event_t event;
 
@@ -1161,13 +1164,8 @@ void QXcbWindow::setWindowState(Qt::WindowStates state)
         }
         m_minimized = true;
     }
-    if (state & Qt::WindowMaximized)
-        setNetWmState(true,
-                      atom(QXcbAtom::Atom_NET_WM_STATE_MAXIMIZED_HORZ),
-                      atom(QXcbAtom::Atom_NET_WM_STATE_MAXIMIZED_VERT));
-    if (state & Qt::WindowFullScreen)
-        setNetWmState(true, atom(QXcbAtom::Atom_NET_WM_STATE_FULLSCREEN));
 
+    // set Maximized && FullScreen state if need
     setNetWmState(state);
 
     xcb_get_property_cookie_t cookie = xcb_icccm_get_wm_hints_unchecked(xcb_connection(), m_window);