iPhone web 应用程序 - 触摸和手势事件

Question

looking at the (quite outdated) documentation on the apple website and across the internet for the touch and gesture javascript events, I can't help but notice that the gesture event which is returned during the function being called, only contains the values 'scale' and 'rotation'. Have I missed something or are they the only two values returned?

It's hard to see the values of a returned object on the iPhone as they are annoyingly only shown as their type and name. eg when logging the returned object in the console, it just shows up as '[object TouchEvent]'.

What I am trying to achieve is to run a function once a two finger swipe occurs, then whether the swipe was left or right, change the page accordingly.

I have tried a more complex touchevent and the (what I thought would be easier) gestureevent, but the gestureevent only returns the scale and rotation (apparently), and the touchevent seems quite complex in the way I am doing it.

Does anyone know if the object returned is just the scale and rotation, and if so, do you know how I can get the same effect with the touchevent instead?

Answer 1

You should use touchevent that provides you trajectory [of movements] to detect is this trajectory falls into "swipe" category using your own definition of swipe.

Usually "swipe" gesture is context specific: eg it should start in particular DOM element and probably end there. It means that for particular DOM element some gesture is not a "swipe" but for its container for example it is a swipe. So you cannot generate bubbling event for that in general.

Zoom and rotation gestures can be detected without knowing context - so system generates them for you.

There are ready to use frameworks and libraries that have swipe gesture detectors. At least for some popular containers like items in vertical list and so on.