Publishing the Expand(object dataItem) Method in the RadTreeView

[LZI]

Expanding an element chain in the TreeView is quite cumbersome when using different descriptors with different templates, as the provided method Expand(IEnumerable itemPath) requires complex preparation and, depending on the context, different preparation mechanisms.

It would be desirable if the already existing method Expand(object dataItem) from the TreeViewAdapter could be made accessible directly through the TreeView.

As an additional bonus, it would be beneficial if the chain could be determined automatically based on the passed element.

[Didi]

Hello Lukas,

Thank you for the provided details.

I have created a sample app using the Expand command and Expand method. The command uses as a parameter the text entered in an Entry, there is a placeholder how the text should be entered. Also a converter to convert the text into a item path.

The method Expand is called inside the Button.OnExpandedClick event. And the code does the following:

•	Finds the root node named Folder 1 from vm.FileSystemNodes (filters to FolderNode only with OfType<FolderNode>()).
•	From that parent’s Children, finds the child folder named Folder 2.
•	If both exist, builds the item path using identity values (strings) based on the TreeViewDescriptor.IdentityMemberPath="Name":
•	var itemPath = new object[] { parent.Name, child.Name };
•	Calls treeView.Expand(itemPath) which expands the node identified by that path.

I hope the example will be of help to get started using this functionality.

Regarding to the Expand(object dataItem) could you please review the Expand implementation I developed on a button click and let me know what is missing from the scenario you requested? In the current TreeView.Expand implementation you need to pass the itemPath. The proposed method signature from your side is the dataItem.

Regards,
Didi
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