sync: from linuxdeepin/dtkwidget

Synchronize source files from linuxdeepin/dtkwidget.

Source-pull-request: linuxdeepin/dtkwidget#704

Author: deepin-ci-robot

src/widgets/private/startupnotifications/startupnotificationmonitor.cpp

@@ -77,11 +77,22 @@ StartupNotificationMonitor::StartupNotificationMonitor() :
         return;
 
     int screen = 0;
-
     xcb_screen_t *s = xcb_aux_get_screen (QX11Info::connection(), screen);
-    const uint32_t select_input_val[] = { XCB_EVENT_MASK_PROPERTY_CHANGE };
-    xcb_change_window_attributes (QX11Info::connection(), s->root, XCB_CW_EVENT_MASK,
-                                  select_input_val);
+    xcb_get_window_attributes_cookie_t attr_cookie = xcb_get_window_attributes (QX11Info::connection(), s->root);
+    xcb_get_window_attributes_reply_t *attr_reply = xcb_get_window_attributes_reply (QX11Info::connection(), attr_cookie, NULL);
+
+    if (attr_reply) {
+        uint32_t old_event_mask = attr_reply->your_event_mask;
+        if (!(old_event_mask & XCB_EVENT_MASK_PROPERTY_CHANGE)) {
+            const uint32_t select_input_val[] = { XCB_EVENT_MASK_PROPERTY_CHANGE | old_event_mask };
+
+            xcb_change_window_attributes (QX11Info::connection(), s->root, XCB_CW_EVENT_MASK,
+                                          select_input_val);
+        }
+        free(attr_reply);
+    } else {
+        qWarning() << "can not get xcb window attributes reply";
+    }
 
     display = sn_xcb_display_new (QX11Info::connection(), NULL, NULL);