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Back in the days of iTunes 6 and its predecessors, the iTunes source pane contained a Library playlist that contained all of your digital content-both audio and video. With the advent of iTunes 7 (and continuing with iTunes 8), this all-encompassing playlist vanished, as it was replaced with a number of different libraries, separated by type of content. While this new approach makes sense for many users, what if you preferred the all-in-one solution?
One way to get back an all-encompassing playlist is to simply create one yourself; there are any number of ways to do this using a Smart Playlist.
The method I use is to create a new smart playlist (Command-Option-N) and then set the condition to Size - is greater than - 0MB, and check the Live Updating box. That's it; you've now got a smart playlist that will show you everything in iTunes, and update each time you add new content.
If you prefer, you could set the criteria to Kind - is not, and leave the last box blank. This, too, will select everything in your iTunes collection.
But what if you really want a combined library view, not a Smart Playlist? As a library, this entry would appear well above Smart Playlists, and would also allow you to rename your iTunes library, which is something you couldn't otherwise easily do.
Quit iTunes if it's running, open Terminal (in Applications -> Utilities), and enter these two commands (the $ is just the prompt; don't type that), pressing Return after each:
$ defaults write com.apple.iTunes show-library-playlist -bool TRUE$ defaults write com.apple.iTunes hide-library-playlist -bool FALSE
Note that the second command may not be required-on one of my machines, this trick worked after only running the first command. On a second machine, however, I had to use both commands.
Now restart iTunes, and notice the new Library entry in the Library section of the iTunes side panel. Click on it, and you'll see that it contains absolutely everything-music, TV shows, movies, podcasts, etc.-in iTunes.
As noted, you can also rename this new entry, so you're not stuck looking at Library as both the title and first entry for the section. Just double-click on the Library entry (the one within the Library section) and type your new name, and you're good to go.
If, for some reason, you'd like to remove this combined view, just quit iTunes, then reverse the previous two Terminal commands:
$ defaults write com.apple.iTunes show-library-playlist -bool FALSE$ defaults write com.apple.iTunes hide-library-playlist -bool TRUE
While many people will find a combined Smart Playlist more than sufficient for their needs, this solution is perfect for those who have long lamented the passing of iTunes' consolidated library view.
Read article at Macworld.com