Single macro that can manipulate any shape that's clicked in slide show view
Problem
You want to do something to a shape when it's clicked in slide show view, but you don't want to write separate macros for each shape.
Solution
Try the following code:
Sub DoItToMe( oShape as Shape )
With oShape
' Add code here to do whatever you like with the shape
' This will make it unfilled if filled or vice versa
.Fill.Visible = Not( .Fill.Visible )
End With
End Sub
For each shape you want to be able to "toggle", select it, right click it, choose Action Settings.
In the Action Settings dialog box, choose Run Macro and pick DoItToMe from the list of macros.
Now when you click the shape in slide show view, it will unfill if filled or fill if unfilled.
See How do I use VBA code in PowerPoint? to learn how to use this example code.