You could use the Get(ApplicationVersion) function to automatically tell which platform they are on and send them to the appropriate layout.
Here is the official FileMaker definition of the function:
If [PatternCount(Get ( ApplicationVersion );"iPad")]
Go to Layout ["iPad"]
Else If [PatternCount(Get ( ApplicationVersion );"Go")]
Go to Layout ["iPhone"]
Go to Layout ["Desktop"]
Hope that helps, if you specifically want to make a dialog box, and not do it automatically, then you could create a value list with a script trigger on modify.
A couple of different ways.
1) You can associate a global field with a button in the Set Custom Dialog script step. You can capture that selection with the Get ( LastMessageChoice ) function. Then, use a series of If [ ] and Else If [ ] statements to go to the layout you want.
2) You can build a layout that has three buttons on it. Each button executes a script, Go to Layout [ calculation ], then use a script parameter on each button to tell FileMaker which layout to go to.
P.S. Another way to look at this would be to use Get ( ApplicationVersion ) to return what version of FileMaker is running - desktop, iPad or iPhone - and have FileMaker automatically go to the correct layout without prompting the user at all.
Ben and Mike,
I do appreciate your help. I think the simplest way is to use the Get (ApplicationVersion). Works like a charm!