Make QWindow update its screen when moved to a different one

Also implements the Cocoa backend for that.

Change-Id: I32977e12a04e1cf48b12333442482746c69ce133
Reviewed-by: Samuel Rødal <samuel.rodal@digia.com>
Reviewed-by: Gunnar Sletta <gunnar.sletta@digia.com>

1 files changed, 20 insertions, 14 deletions

diff --git a/src/gui/kernel/qwindow.cpp b/src/gui/kernel/qwindow.cpp
index 918c2e0b97..68ba1901c1 100644
--- a/src/gui/kernel/qwindow.cpp
+++ b/src/gui/kernel/qwindow.cpp
@@ -345,6 +345,25 @@ void QWindowPrivate::updateVisibility()
         emit q->visibilityChanged(visibility);
 }
 
+void QWindowPrivate::setScreen(QScreen *newScreen, bool recreate)
+{
+    Q_Q(QWindow);
+    if (newScreen != q->screen()) {
+        const bool shouldRecreate = recreate && platformWindow != 0;
+        if (shouldRecreate)
+            q->destroy();
+        if (screen)
+            q->disconnect(screen, SIGNAL(destroyed(QObject*)), q, SLOT(screenDestroyed(QObject*)));
+        screen = newScreen;
+        if (newScreen) {
+            q->connect(screen, SIGNAL(destroyed(QObject*)), q, SLOT(screenDestroyed(QObject*)));
+            if (shouldRecreate)
+                q->create();
+        }
+        emit q->screenChanged(newScreen);
+    }
+}
+
 /*!
     Sets the \a surfaceType of the window.
 
@@ -1568,20 +1587,7 @@ void QWindow::setScreen(QScreen *newScreen)
     Q_D(QWindow);
     if (!newScreen)
         newScreen = QGuiApplication::primaryScreen();
-    if (newScreen != screen()) {
-        const bool wasCreated = d->platformWindow != 0;
-        if (wasCreated)
-            destroy();
-        if (d->screen)
-            disconnect(d->screen, SIGNAL(destroyed(QObject*)), this, SLOT(screenDestroyed(QObject*)));
-        d->screen = newScreen;
-        if (newScreen) {
-            connect(d->screen, SIGNAL(destroyed(QObject*)), this, SLOT(screenDestroyed(QObject*)));
-            if (wasCreated)
-                create();
-        }
-        emit screenChanged(newScreen);
-    }
+    d->setScreen(newScreen, true /* recreate */);
 }
 
 void QWindow::screenDestroyed(QObject *object)