Question

我想显示约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？

我的设置如下：

-(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
    }
}

Answer 2

您可以制作一个在2秒后调用的方法并关闭警报视图并执行您想要执行的任务。

您可以按如下方式调用该方法 -

[self performSelector:@selector(yourMethodName) withObject:nil afterDelay:2];

Answer 3

使用您想要的延迟设置NSTimer（2秒）。在计时器的委托中，使用适当的参数调用UIAlertView的委托。

Answer 4

当您显示警报（非重复）时启动NSTimer并在委托回调中取消它。如果计时器触发，则关闭警报并调用后续任务。

Answer 5

试试这个：

[NSTimer scheduledTimerWithTimeInterval:2.0 target:self selector:@selector(popViewAfterMessage) userInfo:nil repeats:NO];

-(void) popViewAfterMessage {
    // your code here...
}

Answer 6

以下是逻辑..

临时警报约2秒钟，让用户有机会取消操作。



设置标志变量以获取指示天气是否继续。
如果用户单击取消按钮，则不会调用后续方法。



只要UIAlertview出现在用户面前并且设置标志为false，就启动计时器2秒钟。
但是，如果用户没有按下取消，则会调用后续方法。



隐藏UIAlertview，停止2秒计时器＆amp;标志值为true，并调用后续方法继续使用逻辑。

Answer 7

使用此代码：

[NSTimer scheduledTimerWithTimeInterval:2.0 target:self selector:@selector(FunctionName) userInfo:nil repeats:NO];
-(Void)YourFunctionName
{
}

Answer 8

如果您的应用在显示的警报视图后进入后台，则会运行。

UIBackgroundTaskIdentifier bgTask = 0;
    UIApplication  *app = [UIApplication sharedApplication];
    bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
        [app endBackgroundTask:bgTask];
    }];

   NSTimer* currentTimer = [NSTimer scheduledTimerWithTimeInterval:2 target:self
                                                  selector:@selector(YourMethodName) userInfo:nil repeats:YES];

享受!! ....

Answer 9

使用此功能：

- (void)hideAllAlerts {

    for (UIWindow* window in [UIApplication sharedApplication].windows) {
        NSArray* subviews = window.subviews;
        if ([subviews count] > 0)
            if ([[subviews objectAtIndex:0] isKindOfClass:[UIAlertView class]])
                [(UIAlertView *)[subviews objectAtIndex:0] dismissWithClickedButtonIndex:[(UIAlertView *)[subviews objectAtIndex:0] cancelButtonIndex] animated:NO];
    }
}

更改密码：

-(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];
    [NSTimer scheduledTimerWithTimeInterval:2.0 target:self selector:@selector(hideAllAlerts) userInfo:nil repeats:NO];

    return;
}

Answer 10

 [self performSelector:@selector(sendMail) withObject:nil afterDelay:1.0];

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

10 个答案: