Question

I think this has probably been asked, but after reading a lot, I’m not sure I have found an answer.

When the app is rotated to landscape, I’m adding a new view to the main view. The new view is constructed and added in code like this:

UIView * newView = ....
[rootView addSubview:newView];

But because the simulator is rotated to landscape when I add the new view I get this:

+------------------------------------------------------+
+  +---------------------------------------------+     +
+  |                          |                  |     +
+  |                          |                  |     +
+  |      newView             |   rootView       |     +
+  |      (Landscape          |   (Landscape)    |     +
+  |   but portrait size)     |                  |  () +
+  |                          |                  |     +
+  |                          |                  |     +
+  |                          |                  |     +
+  |                          |                  |     +
+  +---------------------------------------------+     +
+------------------------------------------------------+

So I added newView.bounds = rootView.bounds; newView.center = rootView.center; thinking that would position the newView directly over the top of the rootView, but instead I got this:

+------------------------------------------------------+
+  +---------------------------------------------+     +
+  |                                             |     +
+  |                                             |     +
+  |--------------------------+   rootView       |     +
+  |                          |   (Landscape)    |     +
+  |         newView          |                  |  () +
+  |  (Landscape size,        |                  |     +
+  |   but offset)            |                  |     +
+  |                          |                  |     +
+  |                          |                  |     +
+  +---------------------------------------------+     +
+------------------------------------------------------+

I’m trying to figure out why they are different even though I’ve set the bounds and centers to be the same.

Dumping out the views I get this:

 rootView; frame = (0 0; 768 1024); transform = [0, -1, 1, 0, 0, 0]; autoresize = W+H; layer = <CALayer: 0x98870a0>>
 newView ; frame = (-128 128; 1024 768); autoresize = W+H; layer = <CALayer: 0x6e470a0>>

So it appears that the rootView is still 768w x 1024h, just rotated by a transform, and after setting bounds and centre, the new view is 1024w x 768h and offset by 128 points.

Answer 1

After some more playing around, I came up with this:

 // Position the new view offscreen.
CGFloat width = rootView.bounds.size.width;
CGFloat height = rootView.bounds.size.height;
newView.frame = CGRectMake(0, height, width, height);
[rootView addSubview:newView];

 // Animate to the center of the view.
[UIView animateWithDuration:1.0 animations:^{
    newView.frame = CGRectMake(0,0, width, height);
 }];

It works, I’m just wondering if there is a better solution.