Avoid Collapse / Expand for specific items

[Chris1108]

Hello,

is there a way to avoid collapsing and/or expanding tree items depending on the value of a property from the data model ?

 

Additionally a feature request would be helpful: E.g.

Model:

class Node {
  public int Id {get;set;}
  public int ParentId {get;set;}
  public string Name {get;set;}
  public bool IsExpanded {get;set;}
  public bool IsCollapsed {get;set;}
  public bool CanExpanded {get;set;}
  public bool CanCollapsed {get;set;}
}

Bind properties IsExpanded/IsCollapsed to the tree => OnInitial render the node is expanded/collapsed

Bind properites CanExpanded/CanCollapsed to the tree => able to expand/collapse a tree node (and render the indicator differently)

 

[Marin Bratanov]

Hello,

The HasChildren field controls whether an item can be expanded/collapsed, if it is set to false there will be no expand arrow. You can read more about this (there are a few considerations about this) in this article: https://docs.telerik.com/blazor-ui/components/treelist/data-binding/overview

You can use its state to also know when something happens: https://docs.telerik.com/blazor-ui/components/treelist/state - please go through the article as it opens up lots of possibilities - for example, see the StateChanged event and the "Get The User Action That Changes The TreeList" and "Set Default (Initial) State" sections. You can control which items are expanded/collapsed, you can set them on initial load and change what the user does by setting a new state based on the business logic you need to implement.

Regards,
Marin Bratanov
Progress Telerik