links for 04/02/2011
-
jQuery drag & drop fallback strategy for mobile touchscreen devices: tap-to-lift => tap-to-drop.
Only partially convinced; weird experience.
Just tested on IOS browser, Android 2.2 and 2.3 browser and Firefox beta for Android, works just fine. -
Back To The Code: JavaScript Touch and Gesture Events iPhone and Android
JavaScript Touch and Gesture Events iPhone and Android
There are quite a few sites that describe the touch and gesture events that can be used in the mobile version of WebKit running on iPhone and iPod Touch. There is, however, not so much info with regards to Android. I’ve placed a few links at the bottom of this article that contain information used to compile this brief explanation.
Touch events are a bit like mouse events, but there are some very important differences when it comes to touch vs. mouse:
A touch is very hard to keep steady whilst a mouse can stay at a fixed position – this means that we go from a touchStart event directly to a touchMove event. Unlike a mouse where a mouseDown event is likely to fire without being followed up by a mouseMove event.
There is no mouseOver equivalent since a touch can be discontinuous, i.e., we can get from point A to point B without the need of drawing a continuous line between these points.
A touch is an averaged point taken from the surface area in contact with the pointing device (your finger) translated to pixel coordinates – like finding the centre of a circle. A mouse is very precise and there is no averaging that needs to be done. What I’m trying to say is that a touch is not as accurate as a mouse.
Android and iPhone touch events
Android and iPhone versions of WebKit have some touch events in common:
touchstart – triggered when a touch is initiated. Mouse equivalent – mouseDown
touchmove – triggered when a touch moves. Mouse equivalent – mouseMove
touchend – triggered when a touch ends. Mouse equivalent – mouseUp. This one is a bit special on the iPhone – see below
touchcancel – bit of a mystery
Leave a Reply