InnerShadowView is an Objective C based UIView subview for iOS that adds inner shadow functionality. It is configurable to allow shadows to grow from any or all of the view edges. The view is also IB Designable so you can create and modify the view from within Interface Builder, seeing your changes live.

Usage

Use the InnerShadowView as you would any other UIView. See the property comments for more information.

Animation

Due to the use of CAGradientLayers there are some additional steps needed to match any view frame animation. See the example below for an example of how this is accomplished

CGFloat duration = 0.5f;
self.shadowView.shadowAnimationDuration = duration;
self.shadowView.shadowAnimationTimingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];

[UIView animateWithDuration:duration delay:0 options:UIViewAnimationOptionCurveEaseInOut animations:^{
    // Animate shadowView frame change here. 
} completion:^(BOOL finished) {

}];

Download Source

The complete source can be found on github.