如果未单击alertView的buttonIndex,则在持续时间后执行操作

Question

我想显示一个约2秒的临时警报,让用户有机会取消操作.如果用户单击取消按钮,则不会调用后续方法.但是,如果用户没有按取消,则会调用后续方法.任何人对如何使这项工作有任何想法？

我有一个看起来像这样的设置:

-(void) buttonPress {

    //alert with message and cancel button
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"2 seconds to cancel" 
    message:@"Push Cancel to stop" delegate:self cancelButtonTitle:@"Cancel" 
    otherButtonTitles:nil, nil];
    alert.tag = 1;
    [alert show];
    return;
}

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {

    if (buttonIndex == 0 && alertView.tag == 1) {

        //action cancelled
    }
    else {

        //action not cancelled
    }
}

Answer 1

尝试此操作以在2秒后解除警报:

-(void) buttonPress {

    //alert with message and cancel button
    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"2 seconds to cancel" 
    message:@"Push Cancel to stop" delegate:self cancelButtonTitle:@"Cancel" 
    otherButtonTitles:nil, nil];
    alert.tag = 1;
    [alert show];

    // Create the perform selector method with alert view object and time-period
    [self performSelector:@selector(dismissAlertView:) withObject:alert afterDelay:2];
    return;
}


// Dismiss the alert view after time-Period     
-(void)dismissAlertView:(UIAlertView *)alert
{
    [alert dismissWithClickedButtonIndex:-1 animated:YES];

}

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex {

    if (buttonIndex == 0 && alertView.tag == 1) {

        //action cancelled
        [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(dismissAlertView:) object:alertView];
    }
    else {

        //action not cancelled
    }
}