(option?) use CSS position: fixed whenever possible for navigation bars

[jokeyrhyme]

The scrolling area touch-event hack is necessary on iOS and Android<2.3, but many devices support CSS position: fixed.

In my own testing, web applications have much better performance characteristics for content in the scrolling pane. I've noticed that the web forms kitchen-sink widgets' animations are smoother when compared to the touch-event hacked technique.

This might be a solution to:
#22

[davebalmer]

Good point. This is doable today, but not automatic. Would be good to make this easier.

[jokeyrhyme]

According to this, CSS position: fixed support is undetectable:
https://github.com/Modernizr/Modernizr/wiki/Undetectables

However, in the example for Modernizr.addTest(), they give example code that actually tends to work in a few browsers (although I've noticed it produced false-positives in iOS):
http://www.modernizr.com/docs/#addtest

I'm using the example code with some hard coded user-agent sniffing, which is also what the Wink Toolkit does (although they have a slightly more interesting detection mechanism involving getBoundingClientRect).

[jokeyrhyme]

Oops, wrong button.

[davebalmer]

I use user-agent sniffing in my sample apps for this. In one of my apps, I use this to change to native scrolling:

// turn off flick based scrolling
if (!jo.matchPlatform("ios ipad iphone hpwos webos playbook android bada playbook")) {
    joDOM.loadCSS("css/browser.css");
    joScroller.prototype.onDown = function() {};
}

The browser.css file here just reverts back to overflow: auto for divs, but the same sort of approach could be used to also change from position: absolute to position: fixed for certain elements. This sort of thing is something I could see moving into the core library, but I want to do it cleanly.