Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.javascript > #18976

Re: Setting focus

Show key headers only | View raw

Scott Sauyet wrote:

> Thomas 'PointedEars' Lahn wrote:
>> Tim Slattery wrote:
>>> field = document.getElementById("newbox");
>>
>> var field = …
>>
>>> setTimeout("field.focus()", 50);
>>
>> var t = window.setTimeout(function () {
>> field.focus();
>> window.clearTimeout(t);
>> field = null;
>> t = null;
>> }, 50);
>>
>> That is, of course, also only a temporary workaround.
> 
> Of course, but if you're going down this path, why not something as
> simple as
> 
>     (function() {
>         var field = …;
>         window.setTimeout(function () {
>     field.focus();
>         }, 50);
>     }());

Because it is insufficient.
 
> Your code suggests of course that the function associated with the
> setTimeout call will live well beyond the time when it's fired,

“The function” (the Function instance) “will live” (may exist) “well beyond” 
(beyond) the time when it is “fired” (called).

> and so the properties in the related closure should be cleaned up.

_Variables_, not properties.

> I've never run across that.

I am not surprised.

> Do you have any demonstrations of it

Not at the moment.

> or references that discuss it?

Yes.

> I have my doubts because it seems to me that if it were the case, pages
> with heavy animations would often quickly overload the memory.

Not necessarily.

> But I'd love to hear more.

Closures are discussed in the FAQ Notes.

-- 
PointedEars

Twitter: @PointedEars2
Please do not Cc: me. / Bitte keine Kopien per E-Mail.

Back to comp.lang.javascript | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Setting focus Tim Slattery <Slattery_T@bls.gov> - 2013-02-28 14:30 -0500
  Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-28 20:50 +0100
    Re: Setting focus Tim Slattery <Slattery_T@bls.gov> - 2013-02-28 16:05 -0500
      Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-28 22:17 +0100
        Re: Setting focus Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-02-28 23:16 +0100
          Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-02-28 23:36 +0100
            Re: Setting focus Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-03-01 08:21 +0100
              Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-01 13:10 +0100
          Re: Setting focus "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2013-02-28 23:37 +0100
            Re: Setting focus Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-03-01 08:18 +0100
              Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-01 13:12 +0100
                Re: Setting focus Bernd Nawothnig <Bernd.Nawothnig@t-online.de> - 2013-03-02 15:16 +0100
        Re: Setting focus Scott Sauyet <scott.sauyet@gmail.com> - 2013-03-21 20:06 -0700
          Re: Setting focus Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-03-22 10:03 +0100
            Re: Setting focus Tim Slattery <Slattery_T@bls.gov> - 2013-03-22 08:53 -0400
              Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-23 15:09 +0100
            Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-23 15:07 +0100
              Re: Setting focus Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-03-24 12:38 +0100
                Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-24 13:42 +0100
                Re: Setting focus Cezary Tomczyk <cezary.tomczyk@gmail.com> - 2013-03-24 13:54 +0100
          Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-23 15:04 +0100
            Re: Setting focus Scott Sauyet <scott.sauyet@gmail.com> - 2013-03-23 17:35 -0700
              Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-24 10:41 +0100
                Re: Setting focus Scott Sauyet <scott.sauyet@gmail.com> - 2013-03-24 16:42 -0700
                Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-30 14:27 +0100
                Re: Setting focus Scott Sauyet <scott.sauyet@gmail.com> - 2013-03-30 09:25 -0700
                Re: Setting focus Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-03-30 19:50 +0100
                Re: Setting focus Scott Sauyet <scott.sauyet@gmail.com> - 2013-03-30 17:11 -0700
              Re: Setting focus Eric Bednarz <bednarz@fahr-zur-hoelle.org> - 2013-03-30 01:02 +0100
                Re: Setting focus Scott Sauyet <scott.sauyet@gmail.com> - 2013-03-30 09:17 -0700
                Re: Setting focus "Evertjan." <exxjxw.hannivoort@inter.nl.net> - 2013-03-30 17:55 +0100

csiph-web