71000 - [RFE] XUL iframe onload event

Status: VERIFIED WONTFIX

(Core :: XUL, enhancement)

Description

[rvj]

it appears that no onload event is available for XUL iframe/browser/editor 
elements to tell if a document (htm, xml, gif, etc) has loaded or not.

Is this planned and if not could it be? 

When developing UIs some means of letting XUL scripts know when to begin  
processing is needed.  

As a work around, I have attempted to find a method of notifying XUL from the 
document itself but security seems to prevent even this option.

Apologies if this a duplicate (could nt find in XUL component)

Comment 1

[Peter Trudelle]

->hyatt

Comment 2

[Keyser Sose]

Marking NEW.

Comment 3

[David Hyatt]

You do it using iframElt.addEventListener("load", myFunc, true);

Comment 4

[rvj]

Sorry if I'm missing something obvious but I still cant see whats necessary to 
get the iframe load event to fire (attaching xul)

I've even altered the src assignment until after the eventlisterner is added 
(just in case it arrived beforehand) but still no joy.

Even worse the frame does not load at all- is this a separate bug? Thanks.

Comment 5

[rvj]

Attachment: xul test case for onload

Comment 6

[Peter Trudelle]

uh, if it isn't loading, why would you expect its load handler to fire?

Comment 7

[rvj]

ok but that was the last test I tried which seems to show up another bug 
associated with setting the src attribute.

a) should I report it as a separate bug?

modified version of test case with src preset attached

b) can you confirm whether the iframeloaded function fires?

Comment 8

[rvj]

Attachment: simple test case for iframe onload event

Comment 9

[John Morrison]

There is no (to my knowledge) 'src' _property_ for the iframe binding.

The correct way to set the 'src' attribute is through the DOM 'setAttribute'
method, e.g., 
 document.getElementById('someiframe').setAttribute('src','http://www.w3.org');

However, when I add the load listener (either bubbling or capturing), I am
not getting any event notifications (e.g., neither 'load', nor 'click' comes
through). 

Comment 10

[John Morrison]

... although iframe derives from an html iframe which does have that .src
property for its DOM, but the xul iframe is not picking that up from html.

Comment 11

[rvj]

thanks - revised test case now works !

ps I guess that if src is preset the load event is not fired (maybe because it 
has already arrived?)

Comment 12

[rvj]

Attachment: working test case (without preset src)

Comment 13

[rvj]

spoke too soon !

new test case (iframe resized after load event ) results in flashing effect (is 
it continually reloading?)

I know there are a number of onload event bugs pending - is this one of them?

Comment 14

[rvj]

Attachment: flashing effect created after load event fires

Comment 15

[rvj]

and finally  (today)  ..........

I've noticed that the onload event fires fairly reliably for wan http locations 
however this does not seem to be true of lan based http locations .

FYI After clearing cache memory and disc the onload event will fire when the 
XUL application is started. However when the XUL application is subsequently  
restarted it does not.  (a caching issue?)

Comment 16

[David Hyatt]

I already have a bug about adding the src property to iframes and browsers.

Comment 17

[Brian 'netdragon' Bober]

I don't understand, <iframe> has a src in the guide. 
http://www.mozilla.org/xpfe/xulref/iframe.html

Comment 18

[David Hyatt]

This bug is bogus.  Events in the content DOM don't bubble across iframes.  Only
in chrome docshells does this sort of bubbling occur (and HTML iframes have a
hack that allows you to put onload right on the iframe).

If you disagree with this behavior, file an RFE on [e-mail] to request
that events cross iframe boundaries by default in content.

Comment 19

[John Morrison]

Thanks hyatt. Sorry for not getting back to this yesterday. Marking verified.

(To answer boberp last comment: the xul <iframe> has a 'src' _attribute_
( as in <iframe src="..." >), but does not have a 'src' _property_, (as in
document.getElementById('aFrame').src = "...";)

Comment 20

[Brian 'netdragon' Bober]

rvj asked me to clarify the last two comments, and I couldn't because I have no 
idea what was being said. What is docshell?

AFAIK, Mozilla doesn't support iframe onload events.

<iframe onload="alert('Blah')"  src="www.excite.com">

The alert will never fire. bug 60173. Although this isn't a dupe because he is 
talking about XUL.

Comment 21

[John Morrison]

Add this file as 'foop.xul' to your comm.jar package, in the 
/content/navigator/ folder. 

Then enter 
  mozilla -console -chrome chrome://content/navigator/foop.xul




<?xml version="1.0"?> 
<window 
  xmlns:html="http://www.w3.org/TR/REC-html40"
  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
  onload="loadxul();"
  height="400px"
  width="400px"
  align="vertical" > 

<script>
<![CDATA[

var url = ['http://www.mozilla.org/xpfe/',
	   'http://www.mozilla.org/']; 
var idx = 0;

function iframeloaded() {
  dump("iframeloaded\n");
  idx = ++idx % url.length;
  window.setTimeout('foop()', 2000);
}

function loadxul() {
    dump("loadxul\n");
    document.getElementById("iframe").
              addEventListener("load", iframeloaded, true);
    window.setTimeout('foop()', 2000);
}

function foop() {
    dump('foop : ' + url[idx] + '\n');
    document.getElementById("iframe").setAttribute('src', url[idx]);
}

]]>
</script>

<iframe id="iframe" src="http://www.mozilla.org/" flex="1"/>

</window>

Comment 22

[John Morrison]

And yes, it appears that jst has not done the stuff for iframe onload for 
html (bug 60173 as noted).