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Re: Find an object in a window

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On 19/05/2013 12:25 AM, Thomas 'PointedEars' Lahn wrote:
> Andrew Poulos wrote:
>
>> On 16/05/2013 7:12 PM, Thomas 'PointedEars' Lahn wrote:
>>> Andrew Poulos wrote:
>>>> I tried writing a recursive function (that sits in the elearning page)
>>>> that searched all frames in the elearning's top window and in the top
>>>> window of any opener which appears to work:
>>>>
>>>> function findAPI(win) {
>>>>      if (win.API) {
>>>>        return win.API;
>>>>      }
>>>>
>>>>      for (var i = 0; i < win.frames.length; i++) {
>>>          var api = findAPI(win.frames[i]);
>>>          if (api) {
>>>            return api;
>>>>        }
>>>>      }
>>>>
>>>>      if (win.opener && !win.opener.closed) {
>>>>        return findAPI(win.opener.top);
>>>>      }
>>>> }
>>>>
>>>> function fLook() {
>>>>      var foundApi = findAPI(window.top);
>>>>      window.alert(foundApi);
>>>> }
>>>>
>>>> Any ideas on how to make this (more) robust? For example, its not
>>>> checking nested frames.
>>>
>>> Now it does.
>>
>> Too easy! Thanks for the help.
>
> You're welcome.  An omission and a further suggestion on my part, though.
>
> The omission:
>
>    for (var i = 0, len = win.frames.length; i < len; i++)
>
> is more efficient than
>
>    for (var i = 0; i < win.frames.length; i++)
>
> and as safe if you can be sure that the number of items does not change
> while looping.  For that matter, if you stored the value of “win.frames” in
> a variable and access that variable instead, it would be even more
> efficient:
>
>    for (var i = 0, frames = win.frames, len = frames.length;
>         i < len; i++)
>    {
>      var api = findAPI(frames[i]);
>      if (api) {
>        return api;
>      }
>    }
>
> Or you might want to wrap it as suggested e. g. in
> <http://naildrivin5.com/blog/2013/05/17/source-code-typography.html?utm_content=buffer5f552&utm_source=buffer&utm_medium=twitter&utm_campaign=Buffer>
> (from David Bryant Copeland [@davetron5000 at Github], by tweet of
> @kevinSuttle):
>
>    for (var i = 0,
>             frames = win.frames,
>             len = frames.length;
>         i < len; i++)
>    {
>      var api = findAPI(frames[i]);
>      if (api) {
>        return api;
>      }
>    }
>
>
> The suggestion: _it's_ _e-learning_ :)

If the number of frames is, say, 10 or less would it make a noticeable 
difference from the first way or are you promoting a generally better 
approach?

Andrew Poulos

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Find an object in a window Andrew Poulos <ap_prog@hotmail.com> - 2013-05-16 14:49 +1000
  Re: Find an object in a window Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-05-16 11:12 +0200
    Re: Find an object in a window Andrew Poulos <ap_prog@hotmail.com> - 2013-05-16 22:12 +1000
      Re: Find an object in a window Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2013-05-18 16:25 +0200
        Re: Find an object in a window Andrew Poulos <ap_prog@hotmail.com> - 2013-05-19 10:06 +1000

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