drawSystemFocusRing implementation details

Recently (off-list) I had a discussion about the implementation of 
drawSystemFocusRing.

It was my understanding that system generated focus rings would be 
managed by the system, laid atop the Canvas element.
This is in contrast to a  custom focus ring that the author draws and 
manages on their own Canvas bitmap (while still notifying the system).

The current WHATWG spec suggests that drawSystemFocusRing should have 
the system draw a focus ring directly onto the Canvas bitmap.
The W3C spec does not specify, it simply says to "draw" the focus ring.

My thinking is that drawSystemFocusRing should be as easy for authors to 
use as:
element.onfocus = function(e) { ctx.drawSystemFocusRing(e.target); };

That's in contrast to a custom focus ring:
element.onfocus = function(e) { if(ctx.drawCustomFocusRing(e.target)) 
ctx.stroke(); };
element.onblur = function() { myCustomRedrawMethod(); };

Rik, do you have any thoughts on this?

-Charles

Received on Friday, 16 August 2013 15:41:02 UTC