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iOS

Posted by Ben Flannery
Ben Flannery
37 Points

Custom Segue Flicker

I am building an application using UISplitViewController as my root view controller (as prescribed by Apple). However, I needed a custom view for login / management to be displayed prior to the UISplitViewController, so I created a custom UIStoryboardSegue that calls some custom animations. I am attempting to recreate the push / pop segues through a modal segue, without actually pushing an popping view controllers. I've implemented everything correctly, however, at the end of my animation I have a flicker. Here is a gif of it:

Gif of animation

Here is my custom Segue's code: 

- (void)perform {

    UIViewController *srcViewController = (UIViewController *) self.sourceViewController;
    UIViewController *destViewController = self.destinationViewController;

    UIView *prevView = srcViewController.view;

    UIView *destView = destViewController.view;

    UIWindow *window = [[[UIApplication sharedApplication] delegate] window];



    [window insertSubview:destView aboveSubview:prevView];

    [destView enterRight:0.1 then:^{
        [destView removeFromSuperview];
        [srcViewController.presentingViewController dismissViewControllerAnimated: NO completion:nil];

    }];
}

And here is my custom animation (Implemented as a category on UIView): 

-(void)enterRight:(float)delay then:(void(^)(void))after
{
    CGPoint moveTo = self.center;
    CGPoint moveFrom = self.center;


    // Grab a point from off the screen
    CGFloat simpleOffscreen = [UIScreen mainScreen].bounds.size.width;


    // come from off the right side (+)
    moveFrom.x = moveFrom.x + simpleOffscreen;

    self.center = moveFrom;
    self.hidden = NO;

    [UIView animateWithDuration:0.5
                          delay:delay
         usingSpringWithDamping:1
          initialSpringVelocity:0.1
                        options:UIViewAnimationOptionCurveEaseIn
                     animations:^
     {
         self.center = moveTo;
     }
                     completion:^(BOOL finished)
     {
         if (after) after();
     }
     ];
}

As you can see in the Segue, I am animating the view into the current view controller, then without animation presenting the actual destination view controller. I think this is where the flicker is introduced, yet I am unsure about how to go about preventing this.

My Storyboard for this custom segue is Here

Anyone know how to implement this?