Question

I’m building an iPad app with views that are split horizontally and animate in from the top and bottom (think of jaws sliding closed and open to appear and disappear respectively).

My problem is the layout of the custom jaws subview is broken only when the view loads in a landscape orientation. (The jaws-view container loads at the proper size, but the subsequent subviews for the top and bottom half are too tall, and going off the screen. They are the correct width though.)

I can start in portrait and then rotate and everything is arranged correctly.

I’ve tried setting the frame of the new view to the bounds of the original in a bunch of places (as suggested by many answers that didn’t work for me, links upon request) but either haven’t found the right spot, or need something more.

Do I need to do anything special to get the size to propagate? Is there a point before which I should not do animation? (I’m trying to move the top and bottom in my new view controller’s viewDidLoad.)

Answer 1

The solution to this required 2 parts.

The first was described in this answer:
https://stackoverflow.com/a/8574519/1143123
which describes using viewWillAppear method instead of viewDidLoad (called earlier and “incorrect” values for bounds). This solved the problem of the view being layed out properly when loading that view in landscape (and propagated to subsequent rotations).

The second part was that the view could still get messed up if I started animating it and then did a rotation in the meantime. I changed my animation class to only move the center coordinate (as opposed to sliding the frame) which would have been better in the first place, but that didn’t solve it. In the end I hardcoded the following in the ViewController for the class exhibiting these issues:

- (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation {
    [super didRotateFromInterfaceOrientation:fromInterfaceOrientation];

    // The container view should match the size of the current view
    gameView.frame = self.view.bounds;

    CGFloat width = self.view.bounds.size.width;
    if(roundInProgress) {
         gameView.jawsTop.frame = CGRectMake(0, 0, width, self.view.bounds.size.height/2);
         gameView.jawsBottom.frame = CGRectMake(0, self.view.bounds.size.height/2, width, self.view.bounds.size.height/2);

    } else {
        // If round not in progress, game cards should be offscreen
        CGFloat height = self.view.bounds.size.height/2;
        gameView.jawsTop.frame = CGRectMake(0, -height, width, height);
        gameView.jawsBottom.frame = CGRectMake(0, self.view.bounds.size.height, width, height);

    }
}