iphone - 同时调整 UIView 的大小和移动动画

Question

我想将 UIView“拉伸(stretch)”到右侧，这意味着使用 [UIView beginAnimations] 将其frame.size.width增加foo像素，同时将其frame.origin.x减少foo像素句法。但是，如果我这样做，当动画开始时， View 会立即调整大小，然后启动原点的动画。

CGRect currFrame = someView.frame;
currFrame.size.width += 100;
currFrame.origin.x -= 100;

[UIView beginAnimations:@"Anim1" context:nil];
someView.frame = currFrame;
[UIView setAnimationDuration:0.7];
[UIView commitAnimations];

我也尝试过将动画分成两部分，但我无法保持正确的位置。

非常感谢任何帮助!

Answer 1

您可能需要下拉到核心动画并将其分成两个显式动画:

CABasicAnimation *stetchAnimation = [CABasicAnimation animationWithKeyPath:@"transform.scale.x"];
stetchAnimation.toValue = [NSNumber numberWithDouble:(someView.frame.size.width+100)/someView.frame.size.width];

CABasicAnimation *slideAnimation = [CABasicAnimation animationWithKeyPath:@"transform.translation.x"];
slideAnimation.toValue = [NSNumber numberWithDouble:-100];

CAAnimationGroup *animationGroup = [CAAnimationGroup animation];
animationGroup.animations = [NSArray arrayWithObjects:stetchAnimation,slideAnimation,nil];
animationGroup.removedOnCompletion = NO;
animationGroup.fillMode = kCAFillModeForwards;
animationGroup.duration = 0.7;

[someView.layer addAnimation:animationGroup forKey:@"animations"];