[whatwg] HTML 5 drag and drop feedback

[Ian Hickson]

On Thu, 3 Sep 2009, Francisco Tolmasky wrote:
> On Aug 30, 2009, at 7:46 PM, Ian Hickson wrote:
> > 
> > The big thing to realise about this API is that it isn't young -- it's 
> > what IE has shipped for about 10 years, and what Safari has had for a 
> > bit less than that.
> > 
> > We should definitely extend the API going forward, but I'd rather wait 
> > until the browsers implement this set of features reliably before 
> > adding more features.
> 
> I can certainly see the logic behind this, and admittedly my second 
> request (explicitly starting drags) may be particularly difficult to add 
> without changing the spec too much. I will continue to think if there is 
> some trickery that can be done with this.
> 
> However, I think the addition of the deferred setData methods could be 
> added today in a way that is completely backwards compatible with 
> current implementations and would still be of great benefit. 
> Specifically, my request for deferring the calling of toString on 
> non-string objects as such:
> 
> event.dataTransfer.setData("something", { toString: function() { return
> expensiveFunctionCall(); } });
> 
> This would allow me to submit patches to Firefox and WebKit that would 
> solve the current performance issues which are literally blocking my 
> ability to switch from "fake" drag and drop to "native" drag and drop. 
> At the same time, this should still work today in all browsers that 
> implement setData because the object is coerced into a string 
> immediately for you, thus not requiring immediate action on their part 
> to change anything.

Yes, that is a neat solution. However, it is still the case that at this 
time we should not add new features, otherwise we might get too far ahead 
of the implementations, and the quality of implementations will go down.

-- 
Ian Hickson               U+1047E                )\._.,--....,'``.    fL
http://ln.hixie.ch/       U+263A                /,   _.. \   _\  ;`._ ,.
Things that are impossible just take longer.   `._.-(,_..'--(,_..'`-.;.'