UIGestureRecognizer subclass to enable one-finger-zoom gestures.
This concrete subclass of UIGestureRecognizer enables one-finger-zooming (like in the Google Maps iOS app). It has support for elastic bouncing, like UIScrollView does:
If you're going to use this with UIScrollView or want to see it in action make sure to check out BDDRScrollViewAdditions.
Simply add the files in the BDDROneFingerZoomGestureRecognizer.h and BDDROneFingerZoomGestureRecognizer.m to your project or add BDDROneFingerZoomGestureRecognizer to your Podfile if you're using CocoaPods.
There are several properties that change the default behavior, especially interesting are numberOfTapsRequired, minimumPressDuration and allowableMovement. For more info see the header.
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Copyright (c) 2013 Christopher - Marcel Böddecker
Licensed under The MIT License (MIT).