The call canvas.toDataUrl should be synchronous so your timeout would not be 
set until after the call had completed. 

Have you observed asynchronous behavior?

Sent from my iPhone

On 2010-07-20, at 4:48 PM, Excell <[email protected]> wrote:

> I am having some success in achieving what my aim was using simple
> code.
> But I have one question
> 
> I have had to use a setTimeout to wait for the canvas.toDataURL() to
> complete before saveing the data.
> 
> This is not a great way to move forward as depending on the size of
> the image will change the amount of time i would need to set.
> 
> Is there anyway to know when canvas.toDataUrl() is complete
> 
> maybe I am coding this wrong
> 
> Hope that makes sense
> 
> <sample code below>
> function drawImage(img) {
>    var canvas = document.createElement("canvas");
>    canvas.width = img.width;
>    canvas.height = img.height;
>    var ctx = canvas.getContext("2d");
>    ctx.drawImage(img,0,0);
>    var dataURL = canvas.toDataURL();
>    setTimeout(insert(dataURL),2000);//delay enough for the canvas to be
> converted and save to local database
> 
>    //insert(dataURL);
>    //this.cacheImageData(img.src, dataURL);
> }
> 
> Thanks
> 
> Roger[Excell]
> 
> On Jul 16, 7:14 pm, Bill Humphries <[email protected]> wrote:
>> On Jul 16, 2010, at 11:08 AM, Jesse MacFadyen wrote:
>> 
>>> Here's how to get the data from an image.
>>> http://blogs.nitobi.com/jesse/2009/09/24/image-caching-with-the-html5...
>> 
>> Thanks, Jesse. That's much more succinct than my example. Bookmarkiing it.
>> 
>> -- Bill Humphrieshttp://whump.com
> 
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