Should maintain row focus after deleting a file

[roblourens]

• Use the keyboard to focus a file in the explorer and delete it
• Now the whole tree has focus
• Press the down arrow key
• The first item is selected

I want to get back to where I was looking before. The search tree focuses the next item in the list when one is removed. I don't know whether the explorer did this previously with the old tree. But it would be nice for the explorer to do the same thing.

[isidorn]

@joaomoreno currently the tree focuses the tree container when a focused element is no longer in the tree.
Optimally as @roblourens says we shuold just focus the next element in the tree.

Not sure if this should be done on the tree level or on the client level.
Because if we decide to do it in on the client level than we need to imlement this for Search, Explorer, Watch, Breakpoints. Due to multiple clients wanting this same behavior IMHO it makes sense to do this on the tree level.
If you agree to do it on the tree can you provide a code pointer so I look into this?

[roblourens]

This could be some reusable helper that lives outside of the tree. I think search's code for this could be made generic:

https://github.com/Microsoft/vscode/blob/09021f9c8c2d5ae24aec1dd2a8fa79e5dda4baf5/src/vs/workbench/contrib/search/browser/searchActions.ts#L438

[isidorn]

Let's see what @joaomoreno has to say.
But yeah if we need to implement this all over tha place a helper would make sense.

[joaomoreno]

As far as the widget is concerned, it has [A] as the focus group. When A goes away... why would the focus group become [B]? If the focus group would be [A, C] instead and A would go away... should the focus group become [C] or [B, C]?

This should be done on the client level. 👍

[roblourens]

If we work on this we could try to fix #20467 at the same time. That is the case where the ID of the focused item changes. Instead of losing the focus we should try to find a smart way to focus something else.

[brunzefb]

I don't know if this is the same bug: In a large tree, mouse-select a file and use keyboard to delete (cmd-del). The tree scrolls to a random place. I expect no scrolling to take place and the next element in the tree taking the focus.