ios - animateWithDuration 无法识别？

Question

我正在尝试对三个 UILabel(display1、display2、display3)进行交叉溶解，方法是使用 block 动画淡出、更改文本，然后一次淡入一个。我使用的代码是:

[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:'

我使用的是 Xcode 4.0，iOS 构建目标为 4.3。

Answer 1

您想使用

+ animateWithDuration:delay:options:animations:completion:

相反。请注意中间的选项:。