The RadListView is already using the DataSource component internally, adding a 2nd one is not supported.
You can see the data operations you want under the "Features" section in the RadListView documentation
Those are the operations from the internal DataSource component, surfaced through the RadListView API.
Also to be clear, the DataSource component is not available in Xamarin Forms because it's already integrated into the controls. The only time the DataForm is available is if you were building Xamarin.Android or Xamairn.IOS specific projects.
You can see all the UI for Xamarin Cross Platform components here, under the Controls folder
Lance | Tech Support Engineer, Sr.
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