663728 - XUL tree twisty state won't persist if XML template is used

Status: RESOLVED FIXED

(Core :: XUL, defect)

Description

[Hovhannes Babayan]

User-Agent:       Opera/9.80 (Windows NT 6.1; U; en) Presto/2.8.131 Version/11.11
Build Identifier: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0.1) Gecko/20100101 Firefox/4.0.1

I've an XUL tree element with querytype="xml" attribute set. Tree element is populated from XML datasource. Datasource has the following format:
<items>
   <item name="A" id="1">
      <item name="A child 1" id="2"/>
      <item name="A child 1" id="3"/>
   </item>
   <item name="B" id="4">
   <item name="C" id="5">
      <item name="C child 1" id="6"/>
   </item>
</items>

The bug is that tree twisty state won't persist. For example, if I open items A and C using twisty button, they won't stay open after window reload.

For comparison. If RDF datasource is used and "rdf:about"
attribute is present on items A and C, tree remembers twisty state
correctly, that is, if I open children of item A and then reload my
XUL window, item A remains opened.

Reproducible: Always

Steps to Reproduce:
1. Prepare XML datasource with nested levels, with "id" attributes for each item
2. Prepare XUL tree with template, which will generate nested treeitems if recursive datasource is attached
3. Attach XML datasource from step 1 to tree from step 2. Make sure, that tree has nested treeitems, which can be opened/closed using twisty button.
4. Open any treeitem to see its children
5. Reload window

Actual Results:  
Opened treeitem appears closed after reloading window.

Expected Results:  
Opened treeitem should stay opened after reloading window if "id" attribute is present in XML datasource

Such behavior was observed under both 32 and 64 bit Windows for all Firefox/XULRunner versions with XML datasource support.

Comment 1

[Hovhannes Babayan]

Attachment: XUL file with tree template

Comment 2

[Hovhannes Babayan]

Attachment: Sample XML datasource file

Comment 3

[Neil Deakin]

Attachment: fix

This patch fixes this issue.

Two comments about the testcase that would need to be changed:
- an xml id needs to be declared in the xml source
- the patch only works for dont-build-content trees

Comment 4

[Neil Deakin]

Comment on attachment 538968 [details] [diff] [review]
fix

This patch generates the id from the source node's id, rather than using a random value. This way it is always the same each time so persistence can work.

Comment 5

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Comment on attachment 538968 [details] [diff] [review]
fix

Is it documented somewhere how this stuff works? And that we're recommending that you put an id on the relevant elements?

Comment 6

[Neil Deakin]

The idea is that the datasource nodes should have ids if you plan to you the persist feature with them. Persisting of open tree nodes is part of the tree builder, so ids are needed there. However, if you don't want or need persistence, then ids aren't necessary.

Comment 7

[Jonas Sicking (:sicking) No longer reading bugmail consistently]

Sure, but we still need to document this somewhere other than
In this bug.

Comment 8

[Neil Deakin]

My comment 6 is intended to be a summary to be used by someone documenting this.

Comment 9

[Neil Deakin]

http://hg.mozilla.org/mozilla-central/rev/e3a9974fdc28

Comment 10

[Eric Shepherd [:sheppy]]

Looking for suggestions on appropriate places to document this. Would this be one?

https://developer.mozilla.org/en/XUL/treeitem

Any other suggestions? This isn't an area of the docs I've done much with, so I want to be sure to get it right.

Comment 11

[Neil Deakin]

Probably at https://developer.mozilla.org/en/XUL/Template_Guide/XML_Templates or https://developer.mozilla.org/en/XUL/Template_Guide/Building_Trees

Comment 12

[Eric Shepherd [:sheppy]]

Added notes:

https://developer.mozilla.org/en/XUL/Template_Guide/Building_Trees#Using_Tree_Properties
https://developer.mozilla.org/en/XUL/Template_Guide/XML_Templates

And mentioned on Firefox 7 for developers.

Comment 13

[Hovhannes Babayan]

I've added flags="dont-build-content" to XUL tree in the example bug.xul attached above, but treeitem state still doesn't persist.
I am using Firefox 7