xcb: ignore the xscreens which don't belong to current connection

This amends 9a4c98e55659b32db984612e6247ac193812a502.

When a X server has multiple xscreens, for example, ":0.0" and ":0.1",
a Qt application, which uses ":0.1" as display, can't use the randr
monitor from other connection(":0.0") to show contents there. Then
we don't need to generate QXcbScreen for them.

Fixes: QTBUG-110898
Change-Id: I04c1512664b763ffabb55b75db4411d100536255
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>
Reviewed-by: JiDe Zhang <zhangjide@uniontech.com>
Reviewed-by: Liang Qi <liang.qi@qt.io>
(cherry picked from commit 2b94453cbdab5c691c830ff539e81408d5330e3b)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

1 files changed, 12 insertions, 12 deletions

diff --git a/src/plugins/platforms/xcb/qxcbconnection_screens.cpp b/src/plugins/platforms/xcb/qxcbconnection_screens.cpp
index 9e44a322a2..9e8117153c 100644
--- a/src/plugins/platforms/xcb/qxcbconnection_screens.cpp
+++ b/src/plugins/platforms/xcb/qxcbconnection_screens.cpp
@@ -489,6 +489,10 @@ void QXcbConnection::initializeScreensFromMonitor(xcb_screen_iterator_t *it, int
         virtualDesktop = new QXcbVirtualDesktop(this, xcbScreen, xcbScreenNumber);
         m_virtualDesktops.append(virtualDesktop);
     }
+
+    if (xcbScreenNumber != primaryScreenNumber())
+        return;
+
     QList<QPlatformScreen*> old = virtualDesktop->m_screens;
 
     QList<QPlatformScreen *> siblings;
@@ -522,14 +526,12 @@ void QXcbConnection::initializeScreensFromMonitor(xcb_screen_iterator_t *it, int
         siblings << screen;
 
         // similar logic with QXcbConnection::initializeScreensFromOutput()
-        if (primaryScreenNumber() == xcbScreenNumber) {
-            if (!(*primaryScreen) || monitor_info->primary) {
-                if (*primaryScreen)
-                    (*primaryScreen)->setPrimary(false);
-                *primaryScreen = screen;
-                (*primaryScreen)->setPrimary(true);
-                siblings.prepend(siblings.takeLast());
-            }
+        if (!(*primaryScreen) || monitor_info->primary) {
+            if (*primaryScreen)
+                (*primaryScreen)->setPrimary(false);
+            *primaryScreen = screen;
+            (*primaryScreen)->setPrimary(true);
+            siblings.prepend(siblings.takeLast());
         }
 
         xcb_randr_monitor_info_next(&monitor_iter);
@@ -552,10 +554,8 @@ void QXcbConnection::initializeScreensFromMonitor(xcb_screen_iterator_t *it, int
             qCDebug(lcQpaScreen) << "create a fake screen: " << screen;
         }
 
-        if (primaryScreenNumber() == xcbScreenNumber) {
-            *primaryScreen = screen;
-            (*primaryScreen)->setPrimary(true);
-        }
+        *primaryScreen = screen;
+        (*primaryScreen)->setPrimary(true);
 
         siblings << screen;
         m_screens << screen;