iphone - XCODE - 如何 : UIAlertView (with a text field) on a loop until correct value entered into field?

Question

我目前正在 iOS 应用程序上的 Xcode 中工作...

我已经设置了一个 UIAlertView(以问题作为消息)来弹出一个文本字段来检索响应。

所需的功能是，在文本字段中输入不正确的值后，UIAlert 将循环...直到输入正确的响应。此时，UIAlert 将被关闭。

这是我到目前为止所拥有的......

- (void)application:(UIApplication *)application 
didReceiveLocalNotification:(UILocalNotification *)notification {

    NSString* correctAnswer = @"2";


    UIAlertView *alert = [[UIAlertView alloc] 
                          initWithTitle:@"Alarm" 
                          message:@"1 + 1 ="  
                          delegate:self 
                          cancelButtonTitle: nil 
                          otherButtonTitles:@"Continue", nil ];

    alert.alertViewStyle = UIAlertViewStylePlainTextInput;
    UITextField* answerField = [alert textFieldAtIndex:0];
    answerField.keyboardType = UIKeyboardTypeNumberPad;
    answerField.placeholder = @"answer";

    [alert show];


    // I feel like this would work, but I know it doesn't...

    NSString *answerFieldString = answerField.text;
    if ([answerFieldString isEqualToString: correctAnswer ])
    {
        [alert dismissWithClickedButtonIndex:-1 animated:YES];
    }


}

我已经进行了大量的谷歌搜索，但无法找到解决方案...任何回复将不胜感激!

Answer 1

试试这个...

- (BOOL)alertViewShouldEnableFirstOtherButton:(UIAlertView *)alertView
{
     NSString *answerFieldString = answerField.text;
    if ([answerFieldString isEqualToString: correctAnswer ])
    {
        [alertView dismissWithClickedButtonIndex:-1 animated:YES];
    }

}