Animate UIBarButtonItem like Notes app

I just wanted to know how I could copy the trash animation of the Notes.app application. I presume this would include two images and the class of the button is开发者_StackOverflow UIBarButtonItem.

What you're looking to do is either replace the image with an animated image or if it's already an image stack, play the animation.

Switching:

• When the button is released change the Image of the Button to an "animated" Image (array) and play the image stack.
• Once the animation didFinishPlaying (I think) replace the Button Image with the original static/single Image.

(This is much the same way you would easily do it in CSS/HTML.)

Animating:

• When the button is release play the current image stack
• When the animation finishes it's done.

(Basically when there is only one action: play (on release).)

Now, if you want to do the complete animation cycle of the button and the view it becomes a bit trickier, but not too hard.

The Kitchen Sink:

• You need to have the complete image stack of the trash in it's closed state, opening animation sequence and closing animation sequence.
• The releasing on the icon, you start the first half of the animation sequences (opening animation).
• At the end of the sequence (or in parallel) you animate a transition on the view your "deleting" such as warping the view so it scales into the trash.
• When this animation finishes you send the callback/notification/message to the button saying I'm done (play closing animation)
• Then rest at the initial frame of the image stack (closed state).

I don't have the code written for you but I could write pseudo code if you'd like...

Cheers and good luck! (^_^)

In your UINavigationController, this is how you do it:

UIBarButtonItem *clearAll = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemTrash target:self action:@selector(trashMethod)];
self.navigationItem.rightBarButtonItem = clearAll;