A handy demo pattern for you to follow should you want a user interface with a list of files along the left hand edge and something done with those files on the right side of the window.

This is a highly "responsive" PySimpleGUI layout in that it will immediately take action when the user interacts with the window.  You do not need to click a button to indicate a choice was made.  You can also paste the folder path into the input box and the listbox will immediately populare with the correct folder's contents.

![SNAG-0779.jpg](/api/files/5eb18a7c9af9c00e0b7d918b/snag-0779.jpeg "SNAG-0779.jpg")


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