Ch 6: this.body is null error in all browsers

greymouser · September 24th, 2010, 09:24 AM

Hello. I'm working my way through the book, and encountered an issue.

Whenever I try to add a contact to the contact list, the app stops responding. With and error "Uncaught TypeError: Cannot call method 'appendChild' of null" on (around) line ~1345. I've tried this is Chrome, Firefox, and Safari on OSX. I've also tried strophe-1.0.1 and -master -- both have the issue.

It seems 'this.body' in that function is null, and I'm not sure how to proceed.

greymouser · September 24th, 2010, 09:31 AM

I should add that I had to change one line in 1.0.1 and -master.

Line ~1345 reads:
this.node.appendChild(elem);

This works in Firefox, but doesn't work in Chrome. There is a DOM error, relating to access. I /think/ this is because the element is used directly and not copied, so I tried to fix it like this:
this.node.appendChild(elem.cloneNode(true));
... and it seemed to work.

If I revert that fix, I get even less far. :-\

greymouser · September 24th, 2010, 10:24 AM

More updates ....

I originally added the cloneNode(true) code when I couldn't even get the Ch. 3 Hello / ping example to work; that addition solved it. However, since I've added a forward and reverse proxy for the http-bind from my web server to my xmpp server (ejabberd), I find I don't need flXHR. And removing that from Ch.3 and Ch.6 examples made both of them work better.

... Ch. 6 now has a "better error". Chrome gives the easiest to read error backtrace:

Code:

/~fafhrd/foobar/scripts/strophe.js:1505Uncaught TypeError: Object <li id='foxtrot-quarmall-apt'><div class='roster-contact offline'><div class='roster-name'>[email protected]</div><div class='roster-jid'>[email protected]</div></div></li> has no method 'find'
Strophe.Handler.run/~fafhrd/foobar/scripts/strophe.js:1505
(anonymous function)/~fafhrd/foobar/scripts/strophe.js:2792
Strophe.forEachChild/~fafhrd/foobar/scripts/strophe.js:692
Strophe.Connection._dataRecv/~fafhrd/foobar/scripts/strophe.js:2783
(anonymous function)/~fafhrd/foobar/scripts/strophe.js:403
Strophe.Connection._onRequestStateChange/~fafhrd/foobar/scripts/strophe.js:2640
(anonymous function)/~fafhrd/foobar/scripts/strophe.js:403
(anonymous function)/~fafhrd/foobar/scripts/strophe.js:440
(anonymous function)

So ... 1) Proxy in web server to xmpp server, good; flXHR, bad; 2) everything works in most browsers, 'cept for adding contacts to your list in Ch. 6 "Gab".

metajack · December 5th, 2010, 04:34 PM

I believe these types of errors are now fixed. cnode() now uses importNode() to bring in a node.

Let me know if you are still having trouble.