- YMMV with iui, if you use it out of the box, you can create a
generic application quickly, if you want to change how it works, you
have to continue from there onwards. animation is done by tweaking the
style and can lead to less-than-smooth transitions. even Joe changed
the technique in the FB app to use window scrolling instead

- yes, it's a pain to clone data, just to put it side by side, but it
was necessary to get where I have got to. the DOM has a method for
cloning elements which works quickly.

- the processor in today's iPhone is, if memory serves, a 400Mhz chip,
so anything you try to do with regards to Javascript is going to slow
your application down. my advice is, the less Javascript, the better -
render as much as HTML on the server and dish it up.

- GWT is all about Javascript, or at least what I am doing with it
(google for "gwt feed reader" for a good example). I chose to generate
my UI completely in Javascript, which is necessary in some parts, but
otherwise is a choice I'm living with elsewhere. ultimately, it means
you have to tread carefully, not be too processor intensive, and build
things in the background wherever possible.

- use an event model wherever possible. your UI will be unresponsive
while processing Javascript. split this up into chunks and implement a
command scheduler.

/dave

On Jan 18, 8:46 am, "Steve Finkelstein" <[EMAIL PROTECTED]> wrote:
> Hi David,
>
> Thank you for the elaborate reply. It is quite annoying that the execution
> of JavaScript randomly does not occur. It's gotten to the point where I have
> to re-design/re-prototype my entire application because I couldn't figure
> out why it was happening. I'm going to try this time around with iUI,
> although I see you mentioned in your post it was an issue with iUI as well.
> The code GWT is producing seems to be more responsive on your application?
> Basically your solution sounds like making a double of every div that you
> plan on sliding in and out... ouch. That seems a bit bloated, even though it
> might work, I would really like to avoid that as it is a semantic headache.
>
> I'll be trying to re-create my application with iUI and see if anything
> happens. I really wish I did have some solid test cases to report to Apple
> about random javascript instances never being invoked by the browser. I
> cannot replicate any of these symptoms on desktop browsers, eg
> webkit,safari,ff. Only on mobile safari does this become an issue.
>
> Thanks for the reply, I'll see if I can come up with any other solution.
>
> - sf
>
> On 1/12/08, davidroe <[EMAIL PROTECTED]> wrote:
>
>
>
> > On Dec 28 2007, 8:09am, "Steve Finkelstein" <[EMAIL PROTECTED]>
> > wrote:
>
> > > It's almost as if the JavaScript never gets called. I slide a hidden div
> > into view,
> > > and make an XHR call to draw my HTML. I'd say 7 out of 10 times, it will
> > draw
> > > the rest of the div. At least 3 times no POST request is made. Really
> > > disappointing. :-(
>
> > I have spent a long time trying to get around some strange behaviour
> > regarding sliding and Javascript execution. To cut a long story short,
> > I would see perfect behaviour most of the time, but then sometimes the
> > Javascript interpreter would be unresponsive (although it would come
> > back to life if I scrolled the screen).
>
> > Chances are, the only thing our problems have in common is the levels
> > of frustration they are causing and the amount of hair-pulling, but
> > nevertheless, this is what I have finally decided is the cause of it
> > all - large amounts of off-screen content.
>
> > To further explain, you know when you scroll a long web page on Safari
> > on the iPhone/iPod Touch, you have to wait for parts of the display to
> > paint, I presume because the device only holds a certain part of the
> > rendered content in memory and otherwise has to go and build the rest
> > before being able to display it. Well, I think that problems arise
> > when you invoke the Javascript interpreter to scroll content around
> > the display, yet part of this content is buffered and part is not. I
> > don't exactly know what is going on here, but I've been messing around
> > with my particular problem for long enough, running different tests,
> > trying to make any sense of it, and this is the only thing that seems
> > to fit.
>
> > I'm able to say this because I have half a solution in place and am
> > unable to reproduce the problem - I can slide (in one direction, so
> > far) to my hearts content without seeing anything hang. I did this by
> > cloning the div currently displayed, cloning the div that is about to
> > slide in, put each one in a container div with height 480px, overflow
> > hidden, to ensure that displayed content is kept to a minimum, place
> > these two divs side by side and perform the slide, finally putting
> > everything back in place when it is done. And, to be a little more
> > specific, I am sliding using setScroll(), rather than manipulating the
> > div's left style, and am using GWT, not IUI, as my toolkit.
>
> > I hope this helps, in one way or another. I also hope I'm not posting
> > again tomorrow, saying that the problem has returned. I have already
> > wasted plenty of time on this, and I have already thought that the
> > problem had been solved, only to find it turn up again with different
> > content.
>
> > Good luck,
> > /dave

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