[tree view] Trigger manual refresh of lazy loaded children & check parent expansion

[jw3n]

The problem in depth

The lazy loading variant of the MUI RichTreeViewPro component seems to have huge potential to improve code quality and maintainability of the large tree structures. Nevertheless two major problems occurred regarding live updates of the data in the tree:

• There is no possibility to trigger a refresh via api to tell a parent node to reload its children. The only way this could be achieved at the moment is via collapsing and expanding the node via the tree api. But this leads to a bad user experience in the UI
• There is no way to check via the tree api if a node is expanded at the moment or not. This is necessary to determine if a reload has to be triggered for a given parent

Are there any workarounds to achieve the described behavior and/or is it planned to introduce this functionality?

Your environment

`npx @mui/envinfo`

  System:
    OS: Windows 11 10.0.26100
  Binaries:
    Node: 20.11.0 - ~\AppData\Local\Volta\tools\image\node\20.11.0\node.EXE
    npm: 10.2.4 - ~\AppData\Local\Volta\tools\image\node\20.11.0\npm.CMD
    pnpm: Not Found
  Browsers:
    Chrome: Not Found
    Edge: Chromium (136.0.3240.50)

Search keywords: lazy-loading, richt-tree-view, trigger refresh

Order ID: 100621

[michelengelen]

That's a very good question and suggestion,
AFAIK there is no easy way to do this, so you are right in assuming that.

I would like to refer to @noraleonte or @joserodolfofreitas to answer questions about development plans for this. 👋🏼

[noraleonte]

Hey @jw3n 👋
Thanks for raising this. At the moment, there is no solid plan to implement reloading data, but I will push this in our next grooming because it makes complete sense 👌

About expansion, currently there is no way to check if a specific item is expanded or not from the tree view level. You can track when an item's expansion state changes with onItemExpansionToggle or access the status from the item level, but I don't think that helps here 😓

[jw3n]

hey @noraleonte, are there any updates on this?

[noraleonte]

We decided to

• introduce a isItemExpanded to the publicAPI only
• expose fetchItems from the plugin

[github-actions]

This issue has been closed. If you have a similar problem but not exactly the same, please open a new issue.
Now, if you have additional information related to this issue or things that could help future readers, feel free to leave a comment.

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