Android Question DJI Ocusync get/set channel

Sub getChannelNumber
    If aircraft.Connected Then
    Dim airlink As JavaObject = aircraft
    airlink = airlink.RunMethod("getAirLink", Null)
    If airlink.IsInitialized Then
        Dim OcuSyncLink As JavaObject = airlink.RunMethod("getOcuSyncLink", Null)
        If OcuSyncLink.IsInitialized Then
            Dim cc As Object = OcuSyncLink.CreateEventFromUI("dji.common.util.CommonCallbacks$CompletionCallbackWith", "callback", Null)
                OcuSyncLink.RunMethod("getChannelNumber", Array(cc))
            Wait For (OcuSyncLink) Callback_Event (MethodName As String, Args() As Object)
            Log(MethodName)
            Log(Args(0))
            Dim numbers() As Object = Args(0)
            Dim a As List
            a.Initialize
            a.Add(numbers)
            For i = 0 To a.Size-1
                    ChannelNumber = "ChannelNumber "&(a.Get(i))
            Next
        End If
    End If
    Else
        frequency = MethodName &" not connected"
    End If
End Sub