focus() causes focus event to be handled twice in IE8

[easyTree]

Attaching a handler for the focus event to an input/text then focusing the field using focus() causes the handler to run twice in IE8. In firefox, behavior is as expected

Attached is a a simple html page demonstrating the bug.

[easyTree]

Demonstrates that focus handler fires twice when triggered using 'focus()'

[dmethvin]

Not sure what can be done to fix it, but this was also observed by Scott González.

[snover]

Resetting milestone to future.

[john]

I think this is actually very similar to #6593. We're working to try and fix the problem over there for the change event.

[dmethvin]

Confirmed: ​http://jsfiddle.net/dmethvin/gsJyE/

This appears to be fixed in my 1.7 branch, I'll confirm once it lands.

[dmethvin]

Fixed here: ​https://github.com/jquery/jquery/commit/6a670df9e9b9e5cd278b390a2e99ac179307a4e9

[dmethvin]

I had to back out this fix, among other things it was causing focus/blur handlers to not run in cases where the focus/blur method didn't feel they should be fired -- for example, if the element was already focused.

[dmethvin]

I can't think of acceptable solutions that can be implemented at the core level. At present we can either choose to execute the focus handlers either 0-or-1 times (my abandoned patch above) or 1-or-2 times (the current behavior) depending on circumstances, and ensuring that they are run at *least* once seems better than having them not run at all in some cases.

[scottgonzalez]

FWIW, I've talked to Microsoft about this and they don't have an explanation as to why they handle focus asynchronously. They're going to look into making it synchronous for web compat, but that won't happen until after IE10 ships...

[dmethvin]

#12094 is a duplicate of this ticket.

[anonymous]

I had this problem in IE. I used preventDefault() and it stopped the double click for my situation.

[olegku@…]

Hi, we solved this problem using standard focus method of dom element instead of jquery method.

[dmethvin]

@olegku, yes that will sort of work, but note that it will not fire the focus event handlers at all if the element is already focused.