ios - 如何在 Objective C 中为 float 的 UIView 设置动画

Question

我正在尝试将 UIView 设置为 float 对象或气球 :DUIView 位于屏幕中间，我希望它围绕其第一个启动点随机 float 。不跨越屏幕或类似的东西，只是漂浮在它周围 5 个像素的区域内。

有什么建议吗？ :D

我试过这个:

[UIView animateWithDuration:0.1
                      delay:0.0
                    options: UIViewAnimationOptionRepeat | UIViewAnimationOptionAutoreverse | UIViewAnimationOptionAllowUserInteraction
                 animations:^{
                     myCircleUIView.transform = CGAffineTransformMakeTranslation([self randomFloatingGenerator], [self randomFloatingGenerator]);
                 }
                 completion:NULL];

randomFloatingGenerator 生成一个介于 -5 和 5 之间的数字。问题是，它只执行一次，并不断重复相同的随机值。

编辑 1:现在我试过了这个

-(void)animationLoop{

[UIView animateWithDuration:1.0
                     animations: ^{ myCircleUIView.transform = CGAffineTransformMakeTranslation([self randomFloatingGenerator], [self randomFloatingGenerator]); }
                     completion:
     ^(BOOL finished) {
         [UIView animateWithDuration:1.0
                          animations:^{ myCircleUIView.transform = CGAffineTransformMakeTranslation(0,0);
                          }
                          completion:
          ^(BOOL finished) {[self animationLoop];}];
     }];

但它仍然无法正常工作，动画是......糟糕......我想我正在犯一些愚蠢的错误，我需要另一双眼睛来帮助我。

编辑 2:修复它。

 -(void)animationLoop{
    CGPoint oldPoint = CGPointMake(myCircleUIView.frame.origin.x, myCircleUIView.frame.origin.y);
    [UIView animateWithDuration:1.0
                     animations: ^{ myCircleUIView.frame = CGRectMake(myCircleUIView.frame.origin.x + [self randomFloatingGenerator], myCircleUIView.frame.origin.y + [self randomFloatingGenerator], myCircleUIView.frame.size.width, myCircleUIView.frame.size.height); }
                     completion:
     ^(BOOL finished) {
         [UIView animateWithDuration:1.0
                          animations:^{ myCircleUIView.frame = CGRectMake(oldPoint.x, oldPoint.y, myCircleUIView.frame.size.width, myCircleUIView.frame.size.height);}
                          completion:
          ^(BOOL finished) {[self animationLoop];}];
     }];
}

感谢任何人的帮助。

编辑 3:

有人发布了增强代码。

Answer 1

@Shamy 的解决方案，经过改进、修复和 CPU 安全。

-(void)animateFloatView:(UIView*)view{

    // Abort the recursive loop
    if (!view)
        return;

    CGPoint oldPoint = CGPointMake(view.frame.origin.x, view.frame.origin.y);
    [UIView animateWithDuration:0.6
                     animations: ^{ view.frame = CGRectMake(view.frame.origin.x, view.frame.origin.y - 15, view.frame.size.width, view.frame.size.height); }
                     completion:
     ^(BOOL finished) {

         if (finished) {
             [UIView animateWithDuration:0.6
                              animations:^{ view.frame = CGRectMake(oldPoint.x, oldPoint.y, view.frame.size.width, view.frame.size.height);}
                              completion:
              ^(BOOL finished2) {
                  if(finished2)
                      [self animateFloatView:view];
              }];

         }
     }];
}

每当您想停止动画时(离开 View Controller 时需要)，使用nil 调用该函数，如下所示:

    [self recursiveFloatingAnimation:nil];

不停止动画会导致递归循环无限运行并压垮 CPU 堆栈。