Capture touch events and call specified action

[snwau]

I use Snapshot Stack View within my application as a thumbnail and entry point to the full-screen image browser, there I would like to capture touch events to trigger the view controller transition.

When userInteractionEnabled is YES, if registered, calls specified action on touch up similar to a UIButton.
Touches are obviously ignored if userInteractionEnabled is NO.

Please let me know if other users of this control require finer grain control over touches.