GameCenter登录界面 - 取消按钮按下事件

Question

我出示GameCenter登录界面：

GKLocalPlayer *localPlayer = [GKLocalPlayer localPlayer];
localPlayer.authenticateHandler = ^(UIViewController *viewController, NSError *error) {
     if (viewController != nil) {
         [self presentViewController:gameCenterLoginController animated:YES completion:nil];
     }

我希望在登录屏幕解除后做一些事情。

可以通过两种方式解除登录屏幕：

1. 用户已成功登录
2. 用户驳回了登录屏幕

如何捕捉解雇登录屏幕事件（第二种方式）？

（不，UIViewController生命周期方法不像viewDidAppear:那样触发

Answer 1

以下是我在项目中的表现：

GKLocalPlayer *localPlayer = [GKLocalPlayer localPlayer];
localPlayer.authenticateHandler = ^(UIViewController *viewController, NSError *error) {
     if (viewController != nil) {
         [self presentViewController:gameCenterLoginController animated:YES completion:nil];
     }
     else if (localPlayer.isAuthenticated)
     {
       // user is authenticated -  do what next steps
     }
     else
     {
         NSLog(@“Local player is not authenticated or was canceled”);
         //do thing …
     }