Do Android/webOS devices support multi-touch Javascript events?
On iPhone, iPod touch and (presumably) iPad, Apple has multi-touch event handling available via JavaScript in Mobile Safari. I know the Nexus One recently added multi-touch support via an update, and I believe webOS is also multi-touch enabled. Do Android 2.1 a开发者_如何学Cnd/or webOS have access to multi-touch in the browser, or is this currently exclusive to Apple devices?
The best master tracking for touch events (other than multi-touch! - answered above) appears to be:
http://quirksmode.org/mobile/tableTouch.html
Right now, Android 2.1 gets you pinch/zoom, but that's it. There's no fine-grained multi-touch tracking, like you get on iPhone.
UPDATE: MAY 2011 - Android Honeycomb 3.0 and 3.1 browsers now have proper multitouch
Please star this bug on the Android bug list:
http://code.google.com/p/android/issues/detail?id=11909
Let's see if we can raise awareness of this issue.
On Palm webOS, you can get multiple touch events. You can receive up to five touch points at one time.
If you're doing native development using the PDK, handling multiple touches is described at http://developer.palm.com/index.php?option=com_content&view=article&id=1980&Itemid=337. Each finger is tracked as a separate mouse in the SDL events.
For Javascript developers using the standard SDK, there events that are sent to indicate that two fingers are in use. "gesturestart" fires when the user puts 2 fingers on the screen, usually to pinch or rotate, "gesturechange" fires when 1 or both fingers move on the screen, and "gestureend" fires when the fingers are lifted from the screen. These aren't well documented on the Palm developer site, but they're used in the mojomatters sample code.
Edit: looking at your question again, there is no "touch" event support in the browser on WebOS for applications delivered through web sites.
It depends on the browser. The browser on the HTC Hero, which currently runs Android 1.5 and HTC's customised TouchFlo interface, has always had multitouch. The 'Dolphin' browser has also had multitouch since before the Android 2 update. That said, I've never tried using the multitouch for anything but 'pinch zoom' so it might not work with a specific Javascript or something like that.
It depends on the device. But I think the current Android 2.x device got all multitouch.
On the Samsung Galaxy Tab I have tried the Android 2.2 Browser, Dolphin HD 4 and Opera Mini 5. The closest implementation to what I'm looking for is http://anders.com/cms/352/OpenLayers/iPhone/Android/Touch.Gestures (demo ending in '/touchmaps' on that page) which works with the Android 2.2 browser. This does touch pan only with the Android device but no pinch zoom gesture capture in Javascript which is what I really need.
Firefox 4 has the best working and best documented javascript multi-touch API. This is currently implemented in Firefox 4 beta 3 (unfortunately only on Windows 7). I have FF4 beta 2 running on the device but it doesn't have the multi-touch support yet.
I am hoping FF4 b3 for the Android will do what I want, and that the other browser implementation will follow suit. Until then it's just a wait and see.
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