There is (perhaps not documented?) canvas.capabilities, which is
intended to cover this. It's initialized from LzSprite.capabilities,
which is initialized on a per-browser basis. So, I think you just
need to add to that.
On 2009-09-02, at 06:20, Raju Bitter wrote:
I got a good comment on my last blog post showing the CSS text-
shadow features.
http://openfuture.rajubitter.com/2009/08/25/openlaszlo-dhtml-css-3-demo-to-flash-or-not-to-flash-is-no-question/
A guy called Mike said: "Also, I’ve rarely encountered a cross-
platform issue with the Flash Player, which is one of the many
reasons that developers use it. The DHTML/CSS version above doesn’t
display for me in IE7 (I just get the spinning “Powered by…”) but
the Flash below it does."
I thought about that and came to the conclusion - that even for
demos showing the features of HTML 5 and newer CSS standards - I
don't want IE users to only see the spinning "Powered by...".
I added some code to the demo I built, and now - based on the
browser version - you'll see the following message if you access the
application with an old browser or IE:
<OpenLaszlo-CSS-BrowserCheckWarning.png>
That's a much more positive way of informing the user that his
current browser doesn't support the features required for this app.
But I'd be interested in your oppionion, how should we handle
unsupported browsers for DHTML demo apps, especially in future
releases of OpenLaszlo? I thought of a class where you can register
which capabilities your application needs for the full user
experience, with a rating for importance: some features could be
left out, and the application doesn't look as good. Some other
features might be required, and then the user will have to access
the app with a different browser.
For technically interested folks we could have an info button on the
warning message, giving more information about what feature is not
supported in the current browser.
Of course, all of this is not for consumer facing applications in
production, more for the OpenLaszlo demos and docs. In production,
I'd just check the browser and capabilities, and then deliver an SWF
version for the older browsers.
