[PySimpleGUI]How to insert values that were gotten from FilesBrowse into ListBox?

[trigchen]

I want to fill the ListBox with the values when user click the FilesBrowse button and select multiple files and return.
I set the FilesBrowse button's target to the ListBox, it didn't work.
I set the FilesBrowse button's target to (None, None), it didn't fire an event that I can catch after window.Read().
How can I achive the goal with PySimpleGUI?

Thanks advanced.