Android Question RadioButton_CheckedChanged event not firing

Sub Process_Globals
    'These global variables will be declared once when the application starts.
    'These variables can be accessed from all modules.
   
    Dim SaveFileName As String = "SaveFile.txt"
    Dim SavedData As String
End Sub

Sub Globals
    'These global variables will be redeclared each time the activity is created.
    'These variables can only be accessed from this module.

    Private Panel1 As Panel
    Private RadioButton1 As RadioButton
    Private RadioButton2 As RadioButton
End Sub

Sub Activity_Create(FirstTime As Boolean)
    'Do not forget to load the layout file created with the visual designer. For example:
    Activity.LoadLayout("Layout1")

    If File.Exists (File.DirDefaultExternal, SaveFileName) = True Then
            SavedData = File.ReadString(File.DirDefaultExternal, SaveFileName)
            If SavedData = "1.txt" Then
                RadioButton1.Checked = True
                'It only works if I add the line below
                RadioButton1_CheckedChange(True)
            Else
                RadioButton2.Checked = True
                'It only works if I add the line below
                RadioButton2_CheckedChange(True)
            End If
    Else
            SavedData = "1.txt"
            RadioButton1.Checked = True
           
    End If
   
End Sub

Sub Activity_Resume

End Sub

Sub Activity_Pause (UserClosed As Boolean)

End Sub


Sub RadioButton1_CheckedChange(Checked As Boolean)
    File.WriteString(File.DirDefaultExternal, SaveFileName, "1.txt")
    'Do other stuff...
End Sub

Sub RadioButton2_CheckedChange(Checked As Boolean)
    File.WriteString(File.DirDefaultExternal, SaveFileName, "2.txt")
    'Do other stuff...
End Sub