animateWithDuration无法识别？

Question

我正在尝试在三个UILabel（display1，display2，display3）上进行交叉溶解，使用块动画淡出，更改文本然后逐个淡化它们。我正在使用的代码是：

[UIView animateWithDuration:1.0 delay: 1.0
    animations:^{
        display1.alpha = 0.0;
        display2.alpha = 0.0;
        display3.alpha = 0.0;
    }
    completion:^{
        [display1 setText:[NSString stringWithFormat:@"%@",[engine getstring]]];
        [display2 setText:[NSString stringWithFormat:@"%@",[engine getstring]]];
        [display3 setText:[NSString stringWithFormat:@"%@",[engine getstring]]];
        [UIView animateWithDuration:1.0 delay:1.0
            animations:^{
                display1.alpha = 1.0;
                [UIView animateWithDuration:1.0 delay:1.0
                    animations:^{
                        display2.alpha = 1.0;
                        [UIView animateWithDuration:1.0
                            delay:1.0
                            animations:^{
                                display3.alpha = 1.0;
                            } completion:nil];
                    } completion:nil];
        } completion:nil];
    }];

我收到以下警告：

Method '+animateWithDuration:delay:animations:completion:' not found*

和

'UIView' may not respond to method '+animateWithDuration:delay:animations:completion:'

我正在使用Xcode 4.0，iOS Build Target为4.3。

Answer 1

您想要使用

+ animateWithDuration:delay:options:animations:completion:

代替。请注意中间的options:。