viewDidLoad中改變從if語句

Question

我有這樣的代碼

if ([sessionOutput isEqualToString:@"valid"]) { 
    LoggedInViewController *loggedin = [[LoggedInViewController alloc] initWithNibName:nil bundle:nil]; 
    [self presentViewController:loggedin animated:YES completion:nil]; 
} 

除了當它改變視圖我得到這個消息的看法：

Warning: Attempt to present <LoggedInViewController: 0x717fec0> on 
<ViewController: 0x8a64af0> whose view is not in the window hierarchy! 

我到底做錯了什麼？

Answer 1

嘗試將您的代碼移動到viewDidAppear:。
<ViewController: 0x8a64af0>在調用時間viewDidLoad:時尚未添加到視圖層次結構中。

看到這個問題：whose view is not in the window hierarchy