iOS: create top-level UIWindow and UIViewController

Create a UIWIndow with a view controller and a view
where we can reparent our QIOSWindow views inside.

Change-Id: Ic90707d3ebe1af970a3aa2aa0f8c0f4be192456a
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@digia.com>

src/plugins/platforms/ios/qiosapplicationdelegate.mm

@@ -40,6 +40,7 @@
 ****************************************************************************/
 
 #import "qiosapplicationdelegate.h"
+#include "qioswindow.h"
 #include <QtCore/QtCore>
 
 @implementation QIOSApplicationDelegate
@@ -48,7 +49,24 @@
 {
     Q_UNUSED(application)
     Q_UNUSED(launchOptions)
+
+    // If this application delegate is instanciated, it means that
+    // this plugin also created UIApplication. We then also create a
+    // window with a view controller, and set all QWindow views
+    // as children of the controller view:
     self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
+    UIViewController *controller = [[UIViewController alloc] init];
+    self.window.rootViewController = controller;
+    controller.view = [[UIView alloc] init];
+
+    QWindowList windows = QGuiApplication::topLevelWindows();
+    for (int i=0; i<windows.size(); ++i) {
+        if (QIOSWindow *w = static_cast<QIOSWindow *>(windows[i]->handle())) {
+            UIView *winView = w->nativeView();
+            if (winView && !winView.superview)
+                [controller.view addSubview:winView];
+        }
+    }
 
     // Override point for customization after application launch.
     self.window.backgroundColor = [UIColor whiteColor];

src/plugins/platforms/ios/qioswindow.mm

@@ -42,6 +42,7 @@
 #include "qioswindow.h"
 #include "qioscontext.h"
 #include "qiosscreen.h"
+#include "qiosapplicationdelegate.h"
 
 #import <QuartzCore/CAEAGLLayer.h>
 
@@ -170,6 +171,11 @@ QIOSWindow::QIOSWindow(QWindow *window)
     : QPlatformWindow(window)
     , m_view([[EAGLView alloc] init])
 {
+    UIApplication *uiApplication = [UIApplication sharedApplication];
+    if (uiApplication) {
+        if ([uiApplication.delegate isMemberOfClass:[QIOSApplicationDelegate class]])
+            [uiApplication.delegate.window.rootViewController.view addSubview:m_view];
+    }
 }
 
 QIOSWindow::~QIOSWindow()