iOS removeFromSuperview 如果没有添加到 superview 不会抛出错误

Question

I tried removeFromSuperview on a view that had not been added as a subview but Xcode 4 didn't throw any error. Is this expected behaviour?

Answer 1

First off, Xcode 4 wouldn't do anything at all. That's the IDE. It has nothing to do with the runtime behavior of your app.

Secondly, the documentation for -removeFromSuperview states

If the receiver's superview is not nil, the superview releases the receiver.

What part of this would lead you to expect -removeFromSuperview to throw an exception if the view has no superview?

In any case, the answer is yes, this is normal. -removeFromSuperview does not throw exceptions.