[Remoting iOS] Fix screen tearing and screen dimensions

remoting/client/ios/app/host_view_controller.mm

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 #import "remoting/client/ios/app/host_view_controller.h"
 
+#import <GLKit/GLKit.h>
+
 #import "ios/third_party/material_components_ios/src/components/Buttons/src/MaterialButtons.h"
 #import "remoting/client/ios/session/remoting_client.h"
 
 static const CGFloat kFabInset = 15.f;
 
 @interface HostViewController () {
   RemotingClient* _client;
+  GLKView* _gl_view;

[nicholss, 2017/05/01 16:20:14]

Why do you need the gl view to be subview and not the class? You can do
everything you are doing in this cl with self.view vs using gl_view.

Also, iOS coding style calls this _glView.

[Yuwei, 2017/05/01 20:58:08]

I just thought it is easier to reuse the UIViewController's default view. I
don't have a strong opinion though.

Just overrode self.view instead.

 }
 @end
 
 @implementation HostViewController
 
 - (id)initWithClient:(RemotingClient*)client {
   self = [super init];
   if (self) {
     _client = client;
   }
@@ skipping 13 matching lines @@
 
   UIImage* settingsImage = [UIImage imageNamed:@"Settings"];
   [floatingButton setImage:settingsImage forState:UIControlStateNormal];
   [floatingButton sizeToFit];
   CGSize btnSize = floatingButton.frame.size;
   floatingButton.frame =
       CGRectMake(self.view.frame.size.width - btnSize.width - kFabInset,
                  self.view.frame.size.height - btnSize.height - kFabInset,
                  btnSize.width, btnSize.height);
 
+  _gl_view = [[GLKView alloc] initWithFrame:self.view.bounds];

[nicholss, 2017/05/01 16:20:14]

Views in init should be created with CGRectZero and then sized in
layoutSubviews.

[Yuwei, 2017/05/01 20:58:08]

Done. I also needed to fix floatingButton by doing so.

+  _gl_view.enableSetNeedsDisplay = true;

[nicholss, 2017/05/01 16:20:14]

This should move out of the init, you do not know if the controller is in view
or not and this makes extra work that might not be needed. Prob should be in
viewWillAppear:

[Yuwei, 2017/05/01 20:58:08]

Done.

+  [self.view addSubview:_gl_view];
   [self.view addSubview:floatingButton];
 }
 
 - (void)viewDidUnload {
   [super viewDidUnload];
   // TODO(nicholss): There needs to be a hook to tell the client we are done.
 }
 
 - (BOOL)prefersStatusBarHidden {
   return YES;
 }
 
 - (void)viewDidAppear:(BOOL)animated {
   [super viewDidAppear:animated];
-  GLKView* view = (GLKView*)self.view;
-  view.context = [_client.displayHandler GetEAGLContext];
+  _gl_view.context = [_client.displayHandler GetEAGLContext];
+  [_client.displayHandler onSurfaceCreated:_gl_view];
+
+  // TODO(yuweih): Hande new frame when screen rotated.
+  [_client.displayHandler onSurfaceChanged:_gl_view.frame];
 }
 
 - (void)viewWillDisappear:(BOOL)animated {
   [super viewWillDisappear:animated];
 }
 
-#pragma mark - GLKViewDelegate
-
-- (void)glkView:(GLKView*)view drawInRect:(CGRect)rect {
-  // Nothing to do that is synchronous yet.
-}
-
 #pragma mark - Private
 
 - (void)didTap:(id)sender {
   // TODO(nicholss): The FAB is being used to close the window at the moment
   // just as a demo  as the integration continues. This will not be the case
   // in the final app.
   [self dismissViewControllerAnimated:YES completion:nil];
 }
 
 @end