UIWebView HTML 5 game Canvas drawing slowness in iOS 9, or WebGL crashing in iOS 8.0 and above

Question

I've having an issue with UIWebView and running HTML 5 games (that another developer is working on). We've tried two different options, and neither is optimal.

Option 1: He renders the HTML 5 game with "canvas drawing". When he does it this way, nothing crashes, however in iOS 9 when we go back into the app from the background, the Web View loads back up, but the game is moving much slower than normal (issue not on iOS 7.1 and above). By much slower I'm talking about the animations are not moving the same velocity that they were when we first load the game. The weird thing about this issue is that even if the user opens up a different HTML 5 game (we're adding multiple games) the animations are slower for that game as well. I've tried dismissing the Web View Controller when the UIApplicationWillResignActiveNotification gets posted. When I set the game up this way, the slowness only happens if the app is in the for 4 seconds (it's very strange).

Option 2: He renders the game with "WebGL". When he renders it this way, the app crashes when the app gets backgrounded on iOS 8.0 and above. My research into the crash is that iOS can't draw OpenGL ES in the background. I'm assuming that the WebGL commands are running similar commands as OpenGL ES would do, hence the crash. Dismissing the Web View Controller on UIApplicationWillResignActiveNotification still causes the crash to happen.

Has anyone else ever dealt with a situation like this?

Answer 1

I've not found a good solution to the problem, but I did find a work around.

When I get the App Will Resign Active message, I remove the UIWebView from the UIWebViewController's subview. When I get the Did Become Active message, I add the UIWebView to the UIWebViewController's subview.

This solution works for both cases.