Question

I have written this script function

on GetWindowLocation()
    set front_app to (path to frontmost application as Unicode text)
    tell application front_app
        item 1 of (get bounds of front window)
    end tell
end GetWindowLocation

on GetDockStatus()
    tell application "System Events" to get the autohide of the dock preferences
end GetDockStatus

if I am on the desktop with no windows up it errors.
How can I check if a window is on screen, so I can put an if statement to not
run it if a window is not on the screen.

Answer 1

Probably the easiest fix here would be to simply catch the error:

tell application front_app
    try
        return item 1 of (get bounds of front window)
    on error
        -- do something here to handle there being no front window
    end try
end tell

You could also try checking the count of windows before trying to reference the front window, but that’s somewhat more prone to errors (as the window may disappear before you grab its bounds).