ios - NSDate不刷新

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                                6年前关闭。
            
                    
我的第一个视图控制器中的NSDate不会刷新，直到我转到另一个视图控制器，然后再返回它。知道为什么会这样吗？

viewDidLoad：

NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:1.0 target:self selector:@selector(fadein) userInfo:nil repeats:NO];
    [timer fire];

viewWillAppear：

// Date
    NSDateFormatter *formatter = [[NSDateFormatter alloc] init];
    [formatter setDateStyle:NSDateFormatterFullStyle];
    NSString *dateToday = [formatter stringFromDate:[NSDate date]];
    [dateLabel setText:dateToday];
    dateLabel.font = [UIFont fontWithName:@"Helvetica-Bold" size:12];

方法：

-(void) fadein
{
    dateLabel.alpha = 0;
    [UIView beginAnimations:nil context:nil];
    [UIView setAnimationDelay:1.0];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseIn];

    [UIView setAnimationDelegate:self];

    [UIView setAnimationDuration:1.0];
    dateLabel.alpha = 1;

    [UIView setAnimationDidStopSelector:@selector(animationDidStop:finished:context:)];
    [UIView commitAnimations];
}

谢谢！

编辑：问题解决了，这要感谢下面的人提供了有用的答案。看起来其他没有给出答案的人都关闭了问题，但是下面给出了答案的两个人都工作了！

最佳答案

@HotLicks所说的fadeIn很好，但是您要在哪里更改新日期的UILabel？您需要这样做以显示更改的日期，对吗？

-(void) fadein
 {
    //just an example. change this to the format in which you are showing your date.
    NSDate *date = [NSDate date];
    NSDateFormatter *dateFormat = [[NSDateFormatter alloc] init];
    [dateFormat setDateFormat:@"YYYY"];
    uilabelDate.text = [dateFormat stringFromDate:date];
    ....

 }

更新：这是希望为@reez工作的东西-哦，我现在知道了。将此类函数放在viewWillAppear中不是一个好主意，因为有时会缓存视图，并且不会调用此方法。最好将此方法放在viewDidLoad中。看看是否可行...

关于ios - NSDate不刷新，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/16660640/