将转换后的视图添加到UIWindow或UIView后，框架错误

Question

The following code will break the frame (which will be enormous), as seen in iOS 8.1.3.

someView.layer.transform = CGAffineTransformMakeScale(0.001f, 0.001f);
[[[[UIApplication sharedApplication] keyWindow].subviews lastObject] addSubview:someView];

[UIView animateWithDuration:0.3f animations:^{
    someView.transform = CATransform3DIdentity;
}];

Removing the transformation and replacing it with a simple frame movement animation works well. Why?

Answer 1

After some investigation and reasoning I came to the conclusion that it might be a good idea to apply the transformation of someView after it has been added to a view. And this turned out to be the solution. So we write:

[[[[UIApplication sharedApplication] keyWindow].subviews lastObject] addSubview:someView];
someView.layer.transform = CGAffineTransformMakeScale(0.001f, 0.001f);

[UIView animateWithDuration:0.3f animations:^{
    someView.transform = CGAffineTransformIdentity;
}];

Which works as expected.