MinerDataView.DataContext = mdata.MinerList;
You are resetting the data context to the object mdata.MinerList
that goes out of scope because mdata is a local variable.
The WCF call is async, and I see it populate _MinerList but I don't
see where you bind the results. Ideally, you should bind the MinerDataView.DataContext
to a class level object instead of a local variable. Then, in your async callback, repopulate
the class level object's collection. If you use an ObservableCollection<T> as your collection, then Silverlight
will automatically adjust your UI each time the data is loaded.