The UI blocking happens while RadGridView realizes its items. In such case I can suggest you using IsBusy
property of RadGridView and bind it to a boolean property in your view model. You will need to set its value to "true" before the loading process is started and to "false" after the process has finished. You may find the Tips and Tricks
article useful on this matter.
As for your other question, generally, your business object should implement INotifyPropertyChanged
interface in order the client side to be updated.
Please give the two suggestions a try and let me know if I can guide you any further.
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