109760 - DOMContentLoaded event

Status: VERIFIED FIXED

(Core :: DOM: Events, enhancement)

Description

[Allen Tom]

The Quick Checkout Form Fill (QCFF) project would like to have an event fired as 
soon as all the html/css/js has been downloaded. When this event is fired, we 
need access to read/write the dom, especially the form elements.

This event NOT wait for the document's images to load before firing.

This event is intented to give QCFF the opportunity to analyze the forms on a 
document, and begin form filling as soon as possible. The "other" browser engine 
forces us to wait until all the document's objects have loaded or timedout. This 
is particularly bad if one of the images is broken or takes a long time to load.

jst has coded up a patch to nsDocument.cpp for us to try out:

Index: content/base/src/nsDocument.cpp
===================================================================
RCS file: /cvsroot/mozilla/content/base/src/nsDocument.cpp,v
retrieving revision 3.336
diff -u -r3.336 nsDocument.cpp
--- nsDocument.cpp      2001/11/02 01:52:44     3.336
+++ nsDocument.cpp      2001/11/10 06:40:31
@@ -1623,6 +1623,19 @@
       i--;
     }
   }
+
+  // Fire a DOM event notifying listeners that this document has been
+  // loaded (excluding images and other loads initiated by this
+  // document).
+  nsCOMPtr<nsIDOMEvent> event;
+  CreateEvent(NS_LITERAL_STRING("Events"),
+              getter_AddRefs(event));
+  if (event) {
+    event->InitEvent(NS_LITERAL_STRING("DOMContentLoaded"), PR_TRUE, PR_TRUE);
+    PRBool noDefault;
+    DispatchEvent(event, &noDefault);
+  }
+
   return NS_OK;
 }

Comment 1

[Johnny Stenback (:jst)]

Taking.

Comment 2

[Johnny Stenback (:jst)]

Really taking.

Comment 3

[Allen Tom]

Seems to work great! 

Comment 4

[Johnny Stenback (:jst)]

Attachment: Proposed fix, including related leak fix from the trunk...

Comment 5

[Peter Van der Beken [:peterv]]

Comment on attachment 59287 [details] [diff] [review]
Proposed fix, including related leak fix from the trunk...

r=peterv

Comment 6

[Allen Tom]

This needs to be checked into the CompuServe branch, Mozilla 0.94

Comment 7

[rpotts (gone)]

Comment on attachment 59287 [details] [diff] [review]
Proposed fix, including related leak fix from the trunk...

sr=[e-mail]

Comment 8

[Johnny Stenback (:jst)]

Fix checked in on the trunk. Waiting for a day or two to check in on the branch.

Comment 9

[lchiang]

Siva created a testcase for this bug.  I'm attaching it.  

Comment 10

[lchiang]

Attachment: testcase

Comment 11

[lchiang]

pasting comments from chofmann via email:  "how can we test/make sure it won''t
 turn up regressions elsewhere? and possible side effects on performance?"

Comment 12

[Marcia Knous [:marcia]]

EDT - Embedding friends are pulling tomorrow morning. Please check in to 0.9.4.

Comment 13

[Heikki Toivonen (remove -bugzilla when emailing directly)]

Attachment: new testcase

Comment 14

[Heikki Toivonen (remove -bugzilla when emailing directly)]

Oh, you also want to have onload handlers on the images and record the order in
which all of the loadhandlers fire.

Comment 15

[Sivakiran Tummala]

Attachment: testcase with image onload handler

Comment 16

[Sivakiran Tummala]

Tested on build 2001-11-29-09 trunk, and this bug is fixed on the trunk. The 
DOMContentLoaded event is being fired before the image was loaded, and the input 
text value has been changed.

Comment 17

[Johnny Stenback (:jst)]

Fix checked in on the 094 branch.

Comment 18

[Ed]

Too bad that nsIDOMEvent is not a public interface, meaning that it is not 
quite exposed to embedding applications. Recommend to expose it through 
nsIWebProgressListener

Comment 19

[Johnny Stenback (:jst)]

I don't think we need to expose this through nsIWebProgress, in stead we can
simply freeze nsIDOMEventListener, nsIDOMEventTarget, and nsIDOMEvent so that
embedding clients can use those interfaces.

Comment 20

[Ed]

Yes, with nsIDOMEventListener, nsIDOMEventTarget, and nsIDOMEvent we are good 
to go.

Comment 21

[Heikki Toivonen (remove -bugzilla when emailing directly)]

Marking fixed and adding fixed0.9.4 keyword.

Comment 22

[Allen Tom]

For framesets, this event is only fired when the root document is loaded. 

Is there a way to get DOMContentLoaded fired for each frame?

Comment 23

[Johnny Stenback (:jst)]

DOMContentLoaded is fired in every frame as well as in the toplevel
document/frameset. If the toplevel document/frameset needs to know when a frame
in the document is done loading, we'd need a new event for that, something like
DOMFrameContentLoaded. If that's what's needed, then please file a separate bug
on that. Closing again.

Comment 24

[Vladimir Ermakov]

Verifying on windows98 2002-01-07-03-trunk and linux 2002-01-04-08-trunk