Develop example of tree grid design pattern

[mcking65]

This issue depends on issue #91.

URL for Viewing Development Branch

This example is being developed in the treegrid branch. View it at:
https://rawgit.com/w3c/aria-practices/treegrid/examples/treegrid/treegrid-1.html

[aleventhal]

Here's an example I coded up:
https://github.com/aleventhal/treegrid-example

[aleventhal]

Better example, with more discoverable keyboard model:
https://github.com/aleventhal/treegrid-tab-active-cells

[mcking65]

Current work on this example is now in the treegrid branch of w3c/aria-practices at:
https://rawgit.com/w3c/aria-practices/treegrid/examples/treegrid/treegrid-1.html

[mcking65]

In pull request #710, @jongund is working on modifying the example in the treeggrid branch, which is at:
https://rawgit.com/w3c/aria-practices/treegrid/examples/treegrid/treegrid-1.html
to complete the example documentation using the standard example template.

Jon's work can be previewed at:
https://rawgit.com/jongund/aria-practices/treegrid/examples/treegrid/treegrid-1.html

[mcking65]

@aleventhal, what is the reason for using aria-hidden in the treegrid?

[aleventhal]

@mcking65 I believe aria-hidden is just used for the collapsed rows which are hidden. Just semantically indicating that they are in fact hidden.

[mcking65]

@aleventhal commented:

I believe aria-hidden is just used for the collapsed rows which are hidden. Just semantically indicating that they are in fact hidden.

Thanks ... It sounds like we should remove it then.

[aleventhal]

@mcking65 Why is that? Does it work better with the virtual buffer?