Fadein/out文本动画

Question

我正在使用NSTimer(5秒持续时间)和选择器从NSArray中随机选择名称.

这是一些代码

....

NSDate *endtime = [NSDate dateWithTimeIntervalSinceNow:5];

    [NSTimer scheduledTimerWithTimeInterval:0.2 
                                     target:self 
                                   selector:@selector(selectPlayer:) 
                                   userInfo:endtime 
                                    repeats:YES ];

...

-(void)selectPlayer:(NSTimer *)timer
{
    if ([timer.userInfo timeIntervalSinceNow] < 0) 
    {
        [timer invalidate];
    }

    NSString *playerName = [[NSString alloc]initWithFormat:@"%@", 
                            [self.playersNames objectAtIndex:random() & [self.playersNames count]-1]];


    self.playersLabel.text = playerName;
    [playerName release]; 
}

该代码完美地运作.self.playersLabel每隔0.2秒填充一个随机名称.

我想要的是添加一些fadein/fadeout动画效果,同时在playersLabel中更改名称.

怎么实现呢？

Answer 1

您可以使用它来设置文本:

    [UIView animateWithDuration:0.4 animations:^{
        self.playersLabel.alpha = 0;
    } completion:^(BOOL finished) {
        self.playersLabel.text = @"Other text";
        [UIView animateWithDuration:0.4 animations:^{
            self.playersLabel.alpha = 1;
        }];
    }];