Having a dropdown list when calling a function

[Simon Canning]

Here is an example function that I am referring to:

    Public Function testFunction(stringTestString As String, stringChoose As String = {"Example 1", "Example 2"}) As Boolean
        'Do code
    End Function

When I use this function in code, when I select the parameter for stringChoose, I would like a dropdown list to appear that lets me choose either "Example 1" or "Example 2"

How do I do this?