故事板ViewController UI故障

Question

I've got an app that I used Storyboard and autolayout to lay out. I used a UINavigationViewController to programmatically transition between UIViewControllers on button pushes. I used XCode 6 with a minimum iOS version number of 7.1 (tested on iPhone 4s).

I wanted to write a universal interface that would scale to all screen sizes (iPhone, iPad, etc.). In order to do this, I used UIViews that were defined proportionally to screen size to separate the views (please see Figure 1):

Figure 1 - Screenshot of main page of test application

In figure 1 as shown above, the red squares are UIViews that are defined proportionally to screen size that are used to "space out" the "real" views (those that are blue and gray).

Unfortunately, I began to notice that when the user transitioned between UIViewControllers, the views in the view controllers would "resize" (views would move a few pixels or resize by a few pixels) just after transition. This creates the rather irritating experience of the entire interface changing slightly after the user transitions to the appropriate screen.

I culled the project down to a reasonable minimum of code required to produce this resizing effect in hopes that someone could help me out (because I'm at a loss).

Storyboard view hierarchy for 1st view controller:

Constraints for first view controller:

Setup of second view controller:

Code used to transition from 1st to second controller (push):

- (IBAction)transitionForward:(UIButton *)sender
{
    UIViewController *controller = [self.navigationController.storyboard instantiateViewControllerWithIdentifier:@"BackController"];
    [self.navigationController pushViewController:controller animated:YES];
}

Code used to pop from second controller to the first one:

- (IBAction)transitionBack:(UIButton *)sender
{
    [self.navigationController popViewControllerAnimated:YES];
}

As stated, the issue is that the interface appears to slightly resize itself/move around right after the view controller loads after a push/pop triggered by the user clicking on a button. This effect is rather jarring and I would really appreciate any suggestions on how to stop it.

The simplified project that demonstrates the issue can be found at Github .

If there is anything else I can provide, please just ask. Thank you for your time and assistance.

---

Edit: Upon further investigation, it appears that the viewDidLayoutSubviews method of the view controllers is being called twice on view controller transition (in case that helps anyone diagnose the problem).

Answer 1

Try replacing your push and pop function with this code and leme know your requirements are meet or not.

- (IBAction)transitionBack:(UIButton *)sender
{
    CATransition *transition = [CATransition animation];
    transition.duration = 0.45;
    transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionDefault];
    transition.type = kCATransitionFromLeft;
    [transition setType:kCATransitionPush];
    transition.subtype = kCATransitionFromLeft;
    transition.delegate = self;
    [self.navigationController.view.layer addAnimation:transition forKey:nil];


    [self.navigationController popViewControllerAnimated:NO];
}

- (IBAction)transitionForward:(UIButton *)sender
{

    UIViewController *controller = [self.navigationController.storyboard instantiateViewControllerWithIdentifier:@"BackController"];
    CATransition *transition = [CATransition animation];
    transition.duration = 0.45;
    transition.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionDefault];
    transition.type = kCATransitionFromRight;
    [transition setType:kCATransitionPush];
    transition.subtype = kCATransitionFromRight;
    transition.delegate = self;
    [self.navigationController.view.layer addAnimation:transition forKey:nil];


    [self.navigationController pushViewController:controller animated:NO];
}