[wix-users] How to control what files to be installed (Condition)

[Ronny Eriksson]

Hi Eveyone

So i'm not sure if this is possible or not but i ask anyway to see if anyone of you have a solution for it because i can't figure it out.

What i want to do is this.
I want to have a dialog that askes the user if this is a new install or an update of existing installations.
This dialog is not the problem.
But how do I then control what files are installed when choosing the new install or the update existing option?

Can i somehow do a condition on what ComponentsGroupRef/ComponenRef that will be used or something like that and if so how can I do it?
I know I can't do this:
      <ComponentGroupRef Id="MyNewInstallFiles" ><![CDATA[NEWINSTALL]]></ComponentGroupRef>
      <ComponentGroupRef Id="MyUpdateFiles" ><![CDATA[UPDATE]]></ComponentGroupRef>
But that it's essentially what I would like to do... if you understand what I'm think of here.

Any example would be appreciated.
Ronny Eriksson