objective-c - 单击按钮后暂停线程

Question

我有以下代码 - 它创建一个 UIActivityIndi​​catorView 并在单击按钮时执行登录功能。我需要在调用函数之前显示一段时间的活动指示器，所以我做了 sleep(10)，但问题是按钮卡在按下状态（背景颜色从白色变为蓝色并冻结）并且活动指示器视图不显示。当我删除 sleep(10) 时，它工作正常。在创建指示器并且按钮恢复正常状态后，如何暂停线程？

-(IBAction)performLogin{
    UIActivityIndicatorView *view = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
    [view setFrame:CGRectMake(180, 13, 10, 10)];
    [view startAnimating];
    [btnLogin addSubview:view];
    [sleep(10)];    
    if ([self validatePassword] == YES)
    {
        [self performSegueWithIdentifier:@"goToMain" sender:self];
    }
    else
    {
        [ErrorHandler showMessage:@"Wrong password" :@"Authentication"];
    }
}

Answer 1

将您的验证移动到单独的方法，并在延迟后调用它：

-(IBAction)performLogin{
    UIActivityIndicatorView *view = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
    [view setFrame:CGRectMake(180, 13, 10, 10)];
    [view startAnimating];
    [btnLogin addSubview:view];
    [self performSelector:@selector(performPasswordValidation) withObject:nil afterDelay:10];
}

- (void)performPasswordValidation
{
    if ([self validatePassword] == YES)
    {
        [self performSegueWithIdentifier:@"goToMain" sender:self];
    }
    else
    {
        [ErrorHandler showMessage:@"Wrong password" :@"Authentication"];
    }
}