Android: Fix orientation change on Android 4.3

In Android 4.3, we will get a new native window pointer for the
same surface (the old surface has not been destroyed), whereas
before we would get the same pointer, thus hitting the
"sameNativeWindow" branch. This revealed some bugs in the
surfaceChanged code path when the old surface had not been
destroyed. This path is now taken both when there's no old surface
(the app has been suspended in the mean time) and when the
orientation changes.

To handle the second case, we need to make sure:
1. We update the static pointer
2. We update the pointers in the platform windows
3. We don't add a second reference to the static data for
windows
4. We schedule an update of the window size

Task-number: QTBUG-32878
Change-Id: I47257615f9ba820315fc98d7a804e52223f430bf
Reviewed-by: Christian Stromme <christian.stromme@digia.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@digia.com>

4 files changed, 43 insertions, 21 deletions

diff --git a/src/plugins/platforms/android/src/androidjnimain.cpp b/src/plugins/platforms/android/src/androidjnimain.cpp
index 162a8aa977..74183b3107 100644
--- a/src/plugins/platforms/android/src/androidjnimain.cpp
+++ b/src/plugins/platforms/android/src/androidjnimain.cpp
@@ -555,33 +555,37 @@ static void setSurface(JNIEnv *env, jobject /*thiz*/, jobject jSurface)
     m_nativeWindow = nativeWindow;
     if (m_waitForWindow)
         m_waitForWindowSemaphore.release();
-    if (m_androidPlatformIntegration && !sameNativeWindow) {
-        m_surfaceMutex.unlock();
-        m_androidPlatformIntegration->surfaceChanged();
-    } else if (m_androidPlatformIntegration && sameNativeWindow) {
-        QPlatformScreen *screen = m_androidPlatformIntegration->screen();
+
+    if (m_androidPlatformIntegration) {
         QSize size = QtAndroid::nativeWindowSize();
 
+        QPlatformScreen *screen = m_androidPlatformIntegration->screen();
         QRect geometry(QPoint(0, 0), size);
         QWindowSystemInterface::handleScreenAvailableGeometryChange(screen->screen(), geometry);
         QWindowSystemInterface::handleScreenGeometryChange(screen->screen(), geometry);
 
-        // Resize all top level windows, since they share the same surface
-        foreach (QWindow *w, QGuiApplication::topLevelWindows()) {
-            QAndroidOpenGLPlatformWindow *window =
-                    static_cast<QAndroidOpenGLPlatformWindow *>(w->handle());
-
-            if (window != 0) {
-                window->lock();
-                window->scheduleResize(size);
-
-                QWindowSystemInterface::handleExposeEvent(window->window(),
-                                                          QRegion(window->window()->geometry()));
-                window->unlock();
+        if (!sameNativeWindow) {
+            m_surfaceMutex.unlock();
+            m_androidPlatformIntegration->surfaceChanged();
+        } else {
+            // Resize all top level windows, since they share the same surface
+            foreach (QWindow *w, QGuiApplication::topLevelWindows()) {
+                QAndroidOpenGLPlatformWindow *window =
+                        static_cast<QAndroidOpenGLPlatformWindow *>(w->handle());
+
+                if (window != 0) {
+                    window->lock();
+                    window->scheduleResize(size);
+
+                    QWindowSystemInterface::handleExposeEvent(window->window(),
+                                                              QRegion(window->window()->geometry()));
+                    window->unlock();
+                }
             }
+
+            m_surfaceMutex.unlock();
         }
 
-        m_surfaceMutex.unlock();
     } else {
         m_surfaceMutex.unlock();
     }
diff --git a/src/plugins/platforms/android/src/opengl/qandroidopenglplatformwindow.cpp b/src/plugins/platforms/android/src/opengl/qandroidopenglplatformwindow.cpp
index 5362906e0e..b1a2231ff5 100644
--- a/src/plugins/platforms/android/src/opengl/qandroidopenglplatformwindow.cpp
+++ b/src/plugins/platforms/android/src/opengl/qandroidopenglplatformwindow.cpp
@@ -85,9 +85,19 @@ void QAndroidOpenGLPlatformWindow::invalidateSurface()
     }
 }
 
+void QAndroidOpenGLPlatformWindow::updateStaticNativeWindow()
+{
+    QWriteLocker locker(&m_staticSurfaceLock);
+    m_staticNativeWindow = QtAndroid::nativeWindow(false);
+}
+
 void QAndroidOpenGLPlatformWindow::resetSurface()
 {
-    m_referenceCount.ref();
+    // Only add a reference if we're not already holding one, otherwise we're just updating
+    // the native window pointer
+    if (m_window == 0)
+        m_referenceCount.ref();
+
     if (m_staticSurface == 0) {
         QWriteLocker locker(&m_staticSurfaceLock);
         QEglFSWindow::resetSurface();
@@ -95,12 +105,17 @@ void QAndroidOpenGLPlatformWindow::resetSurface()
         m_staticNativeWindow = m_window;
     } else {
         QReadLocker locker(&m_staticSurfaceLock);
-        Q_ASSERT(m_staticSurface != m_surface);
         m_window = m_staticNativeWindow;
         m_surface = m_staticSurface;
     }
 
-    QWindowSystemInterface::handleExposeEvent(window(), QRegion(geometry())); // Expose event
+    {
+        lock();
+        scheduleResize(QtAndroid::nativeWindowSize());
+        QWindowSystemInterface::handleExposeEvent(window(), QRegion(geometry())); // Expose event
+        unlock();
+    }
+
     QWindowSystemInterface::flushWindowSystemEvents();
 }
 
diff --git a/src/plugins/platforms/android/src/opengl/qandroidopenglplatformwindow.h b/src/plugins/platforms/android/src/opengl/qandroidopenglplatformwindow.h
index 36a110e1a8..9a25957ccd 100644
--- a/src/plugins/platforms/android/src/opengl/qandroidopenglplatformwindow.h
+++ b/src/plugins/platforms/android/src/opengl/qandroidopenglplatformwindow.h
@@ -71,6 +71,8 @@ public:
 
     void destroy();
 
+    static void updateStaticNativeWindow();
+
 private:
     QSize m_scheduledResize;
     QMutex m_lock;
diff --git a/src/plugins/platforms/android/src/qandroidplatformintegration.cpp b/src/plugins/platforms/android/src/qandroidplatformintegration.cpp
index 91ad2b368f..636a2b3853 100644
--- a/src/plugins/platforms/android/src/qandroidplatformintegration.cpp
+++ b/src/plugins/platforms/android/src/qandroidplatformintegration.cpp
@@ -162,6 +162,7 @@ void QAndroidPlatformIntegration::invalidateNativeSurface()
 
 void QAndroidPlatformIntegration::surfaceChanged()
 {
+    QAndroidOpenGLPlatformWindow::updateStaticNativeWindow();
     foreach (QWindow *w, QGuiApplication::topLevelWindows()) {
         QAndroidOpenGLPlatformWindow *window =
                 static_cast<QAndroidOpenGLPlatformWindow *>(w->handle());