This article will cover the basic of adding the Three20 framework to your Xcode 4 solutions.
A little background of this particular framework, quoting from the source.
Three20 is a open source Objective-C library used by dozens of well-known brands in the App Store, including Facebook, Posterous, Pulse, Meetup.com, and SCVNGR. Three20 provides powerful view controllers such as the Launcher, the popular Photo Browser, and internet-aware tables.
Another post will be written to discuss about the features of the framework, Three20. But for now let’s us get started on adding this the Three20 to your Xcode 4 project.
Three20 source code could be downloaded from the following link. www.three20.info
I do strongly suggest that you download the tar.gz version.
Start by extracting the content of the file you downloaded from the site.Again, I suggest that you should extract the file on the desktop.
Locate the file ttmodule.py at that paticularly path three20/src/script/
Drag ttmodule.py into the terminal window,
Locate your xcode project, Drag the .xcodeprojfile into the Terminal.
Check that the Terminal Window should now look something like this > python /Users/xxx/Desktop/three20/src/scripts/ttmodule.py -p /TestingProject/TestingProject.xcodeproj Three20
This will add the Three20 framework into the xcode project and you can find out more on how to use the following at the following site.