Pinching and Panning
How can we play with images on iOS? The whole point of a touch interface is to provide the feeling of interacting directly with our data, so we should be thinking of moving the image around with a drag, zooming in and out of it with pinch gestures, and so forth.
Let’s take a look at what gesture recognizers give us. Here’s a table summarizing the concrete subclasses of UIGestureRecognizer and the important properties and/or methods exposed by each:
Class | Important Properties and Methods |
---|---|
UILongPressGestureRecognizer | minimumPressDuration, allowableMovement |
UIPanGestureRecognizer | translationInView:, velocityInView: |
UIPinchGestureRecognizer | scale, velocity |
UIRotationGestureRecognizer | rotation, velocity |
UIScreenEdgePanGestureRecognizer ... |
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