[Solved] Collapse Treelist

Hello, Petteri,

You can configure the expanded state of the items through the TreeList State.

The TreeList exposes two state events:

• OnStateInit - fires when the TreeList is initialized.
• OnStateChanged - fires when the user makes a change to the component's State, like sorting, filtering, paging, editing and so on.

To collapse all items on initialization, handle the OnStateInit event and pass an empty collection to the ExpandedItems field of the state object. See an example here: https://docs.telerik.com/blazor-ui/components/treelist/state#set-treelist-options-through-state.

Let me know if additional information is needed.

Best regards,
Georgi
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