How to detect pinch in gesture vs pinch out gesture?

cocoa-touch, ios, objective-c, uipinchgesturerecognizer

Solution

Well, that seems an easy one. The `UIPinchGestureRecognizer` class has only two properties, `scale` and `velocity`. It seems logical that a negative `scale` would mean an inward pinch, a positive `scale` an outward pinch.

NB: "negative" might be misleading. "Smaller" is `0.0 < scale < 1.0`, "bigger" is `scale > 1.0`.

Problem

Instead of scaling, which I think pinch gesture is usually used for, I am looking to just detect whether the pinch was a pinch in vs pinch out so I can collapse or expand some table sections. How would I go about doing that?

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