Because I have a small 16 GB iPhone which is way less than the size of my music library, I use the “sync only checked items” approach. However, I want podcasts I have listened to already be unchecked as well. For that reason I’ve written this little Applescript which runs through all the podcasts and unchecks the ones I’ve listened to.
tell application "iTunes"
set thetracks to every track of library playlist 1 whose podcast is true and enabled is true and unplayed is false and bookmark is 0
repeat with currentTrack in thetracks
set enabled of currentTrack to false
end repeat
end tell
This was slightly harder than it looks due to the fact that iTunes uses the “unplayed” property to indicate it has never been played, ever. When you’re halfway through, though, a tracks’ “unplayed” is false, but you don’t want to uncheck it. In the iTunes GUI a blue dot indicates played, a half-filled blue dot played but not finished and no blue dot is played and finished. The breakthrough is in the “bookmark” field, which gets set to the position in the file you last listened to. Kindly, Apple sets this to 0 when a track is completely listened all the way, leading to the conditions above.
You can use the AppleScript editor to create this file and save it as “Uncheck heard podcasts.scpt”, then save it in your Library/iTunes/Scripts folder. When you restart iTunes, it will show up in the script menu.
This is a good example of how knowing a scripting language can help you out.