QNX: Fix one more code path that led to having no QScreens.

Qt dereferences QGuiApplication::primaryScreen() inside,
for example, QColormapPrivate::initialize().

libscreen always returns at least one display, even it it's
not connected, so lets not ignore it if it's primary.

Change-Id: I2f14a187c979ca0c7ad39149ceb0b2b7e61e9ba6
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

1 files changed, 11 insertions, 2 deletions

diff --git a/src/plugins/platforms/qnx/qqnxintegration.cpp b/src/plugins/platforms/qnx/qqnxintegration.cpp
index bff4dbdc2a..d7370998d5 100644
--- a/src/plugins/platforms/qnx/qqnxintegration.cpp
+++ b/src/plugins/platforms/qnx/qqnxintegration.cpp
@@ -446,6 +446,11 @@ void QQnxIntegration::createDisplays()
         qFatal("QQnxIntegration: failed to query display count, errno=%d", errno);
     }
 
+    if (displayCount < 1) {
+        // Never happens, even if there's no display, libscreen returns 1
+        qFatal("QQnxIntegration: displayCount=%d", displayCount);
+    }
+
     // Get all displays
     errno = 0;
     screen_display_t *displays = (screen_display_t *)alloca(sizeof(screen_display_t) * displayCount);
@@ -454,7 +459,11 @@ void QQnxIntegration::createDisplays()
         qFatal("QQnxIntegration: failed to query displays, errno=%d", errno);
     }
 
-    for (int i=0; i<displayCount; i++) {
+    // If it's primary, we create a QScreen for it even if it's not attached
+    // since Qt will dereference QGuiApplication::primaryScreen()
+    createDisplay(displays[0], /*isPrimary=*/true);
+
+    for (int i=1; i<displayCount; i++) {
         int isAttached = 0;
         result = screen_get_display_property_iv(displays[i], SCREEN_PROPERTY_ATTACHED, &isAttached);
         if (result != 0) {
@@ -468,7 +477,7 @@ void QQnxIntegration::createDisplays()
         }
 
         qIntegrationDebug() << Q_FUNC_INFO << "Creating screen for display" << i;
-        createDisplay(displays[i], i==0);
+        createDisplay(displays[i], /*isPrimary=*/false);
     } // of displays iteration
 }