An example?

Hi, I'm creating an EA, I would like to be able to choose some indicator parameters when I load the EA. For example, if I use the "adx" indicator, I would like to be able to choose "adx mode" and "apply price" from a drop-down menu in the EA, or when I use the "alligator" indicator I would like to be able to choose "MA method " and "Apply price". Could anyone help me? Thanks everyone.