一个接一个地运行动画失败

Question

我正在尝试对图像进行动画处理，使其在选择时左右旋转，基本上是为了让用户触摸他们正在触摸的对象。

我找到了一些动画代码：

- (void)rotateImage:(UIImageView *)image duration:(NSTimeInterval)duration 
              curve:(int)curve degrees:(CGFloat)degrees delay:(CGFloat)delay
{
    // Setup the animation
    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationDelay:delay];
    [UIView setAnimationDuration:duration];
    [UIView setAnimationCurve:curve];
    [UIView setAnimationBeginsFromCurrentState:YES];

    // The transform matrix
    CGAffineTransform transform = 
    CGAffineTransformMakeRotation(DEGREES_TO_RADIANS(degrees));
    image.transform = transform;

    // Commit the changes
    [UIView commitAnimations];
}

但是，当我尝试运行两个动画时，只有最后一个可以工作。即使有适当的延迟，也只会显示第二个动画：

[self rotateImage:self duration:.5 
                curve:UIViewAnimationCurveEaseIn degrees:60 delay:0];
    [self rotateImage:self duration:.5 
                curve:UIViewAnimationCurveEaseIn degrees:-60 delay:5];

我可以做什么来创建动画，使其向左旋转，然后向右旋转？

Answer 1

[UIView animateWithDuration:0.2 animations:^{
// animation left
    [UIView setAnimationDelay:10];

    } completion:^(BOOL finished){

[UIView animateWithDuration:0.2 animations:^{
       // animation right
    } completion:^(BOOL finished){
       // done
    }];

    }];

在这里找到它

https://developer.apple.com/library/content/featuredarticles/ Short_Practical_Guide_Blocks/

Answer 2

[UIView animateWithDuration:0.5f delay:0.0f options:UIViewAnimationOptionCurveEaseIn animations:^{
    self.view.transform = CGAffineTransformMakeRotation(DEGREES_TO_RADIANS(60));
} completion:^(BOOL finished){
    [UIView animateWithDuration:0.5f delay:5.0f options:UIViewAnimationOptionCurveEaseIn
      animations:^{
        self.view.transform = CGAffineTransformMakeRotation(DEGREES_TO_RADIANS(-60));
      }
      completion:^(BOOL finished){}];
}];

Answer 3

动画块绝对是最佳选择。这应该复制您正在尝试做的事情，包括宽松。这假设您从视图控制器进行调用，但如果您将此代码放入 UIView 或 UIImageView 中，则只需将 self.view 替换为 self 即可。

[UIView animateWithDuration:0.5f delay:0.0f options:UIViewAnimationOptionCurveEaseIn animations:^{
    self.view.transform = CGAffineTransformMakeRotation(DEGREES_TO_RADIANS(60));
} completion:^(BOOL finished){}];

[UIView animateWithDuration:0.5f delay:5.0f options:UIViewAnimationOptionCurveEaseIn animations:^{
    self.view.transform = CGAffineTransformMakeRotation(DEGREES_TO_RADIANS(-60));
} completion:^(BOOL finished){}];