Using the TreeView drag and drop editing directive, the child nodes are moved automatically.
If you want to handle the events manually, it's important to know what is the structure of your data and do you have it loaded locally. When using local hierarchical data, the child items are moved with the parent item. When using local flat data, you will have to acquire the child nodes yourself. The editing directive uses the children function to recursively collect all child nodes. Here's an example. The child nodes of the clicked item are logged to the console.
If that doesn't solve your problem, I'd have to ask for more details about setup, data structure, data availability (local or loaded on demand for each newly expanded node). A runnable example would be best.
Looking forward to hearing back from you.
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