Why does a view changes position when rotating it using CGAffineTransformMakeRotation

Question

I have the following super simple animation, I\'m basically rotating a view 2 radians from its original angle/center, it rotates fine my only misunderstanding is why does the vi

Answer 1

I am adding another answer due to @fs_tigre request. The problem is with the auto layouts in your xib file, unfortunately is it unknown why that affects the transform.
Now here is the steps I did to solve the issue:

1- first you need to get rid off your auto layout (yes, you have to)
uncheck Use Autolayout

2- remove all constraints and autoresizing masks for your view that will be rotated, as in the screenshot (Here I have my blue box, see on the right autoresizing, nothing is selected)

I have made some changes for your rotation's code

self.someView.layer.anchorPoint = CGPointMake(0.5, 0.5);
    // one degree = pi/180. so...
    // rotate by 90
    CGFloat radians = (M_PI/180) * 90;
    [UIView animateWithDuration:1.0 animations:^{
        self.someView.transform = CGAffineTransformRotate(self.someView.transform, radians);
    }];

Click rotate and see the magic :)