If you want to sort a Kendo widget you should sort its dataSource (the widget will be updated automatically).
Within the TreeView widget each level of items is represented with different dataSource instance (hierarchical
dataSource), which means you need to sort all levels of dataSource hierarchy.
Option 1) The most easy way and avoid traversing would be to specify that the dataSource should be sorted upon initialization. This will make that each newly created level will be sorted automatically because of inheritance (because the levels are created when they are expanded).
To specify a sort condition you can use the same approach as the one for the regular dataSource:
Option 2) If you want to sort a TreeView that was already initialized or if you want to change the sorting direction then you will have to traverse the whole tree get the dataSource object for each level and use the sort
method on it.
Check for example this example of traversing to get the idea:
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