Animating the present and dismiss of a Share Extension with custom UI on iOS 8

Here is the cleanest solution I found so far to animate my custom view controller in and out!

Animate IN:

- (void)viewWillAppear:(BOOL)animated{    [super viewWillAppear:animated];    self.view.transform = CGAffineTransformMakeTranslation(0, self.view.frame.size.height);    [UIView animateWithDuration:0.25 animations:^    {        self.view.transform = CGAffineTransformIdentity;    }];}

Dismiss:

- (void)dismiss{    [UIView animateWithDuration:0.20 animations:^    {        self.view.transform = CGAffineTransformMakeTranslation(0, self.view.frame.size.height);    }     completion:^(BOOL finished)     {        [self.extensionContext completeRequestReturningItems:nil completionHandler:nil];    }];}

Instead of animating the UIViewController's view, I am suggesting a bit different approach.

I have created a dummy UIViewController (called PresentingViewController here on) whose view.backgroundColor is set to [UIColor clearColor]. I then present the intended custom UIViewController modally (or custom animation if you like) on top.

This is the code for the PresentingViewController:

@implementation PresentingViewController- (void)viewDidAppear:(BOOL)animated {  [super viewDidAppear:animated];  [self performSegueWithIdentifier:@"PresentController" sender:self];}- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {  if ([segue.identifier isEqualToString:@"PresentController"]) {    CustomViewController *controller = (CustomViewController *)[segue.destinationViewController topViewController];    controller.context = self.extensionContext;  }}- (IBAction)unwindFromShareVC:(UIStoryboardSegue *)segue {  [self dismissViewControllerAnimated:YES completion:^{    NSError *error = [NSError errorWithDomain:@"Cancelled" code:0 userInfo:nil];    [self.extensionContext cancelRequestWithError:error];  }];}@end

Notes:

1. extensionContext is set only on the PresentingViewController and thus it is required to be passed on to the CustomViewController.
2. For animating dismiss, I was unable to use an unwind segue, because it was difficult to know the completion of dismissal. So I used dismissViewControllerAnimated:completion: instead.