Making an alpha matte PIP with border (stroke)

[neilm143998]

How do I add a stroke to these boxes?  

I was able to make two rectangles with shape layers-->pre-comping them-->Track matte with my designed foreground layer.  I was also able to make the mattes by merging the shape layers, but in both instances I was not able to create a white stroke around the boxes (the strokes I added became transparent).   

Thank you

[ShiveringCactus · Accepted solution]

I think there's several ways you could do this.   

1. If you had not precomped, you can have more than one shape on a shape layer, so this solution becomes easier, but: Duplicate your shape layers.  Expand the shapes on the timeline and turn off or delete the Fill components (Edit: to clarify - you'd also move the duplicates out of the precomp and back into the main comp)
   
2. Alternatively, the other option is to use Layer Styles to add a stroke
   

[neilm143998]

That's so great, thank you for the detailed explanation.   I forgot to mention that I did do a version where I drew two shapes on the same layer - much more simple.  I was putting the stroke on the rectangles that I was drawing - It makes much more sense to put the stroke on the foreground layer, otherwise the stroke will always be transparent.