How to find easily the source of an android class

Most things you'll want to see can be found under the frameworks/base repo. This includes pretty much all the public and private API classes that make up the Android Java framework.

If you want to be able to browse the source from within Eclipse, you can follow this guide: http://blog.michael-forster.de/2008/12/view-android-source-code-in-eclipse.html

Finally, the Android SDK Reference Search extension for Chrome lets you browse the public API by typing ad into the URL bar, and it adds a convenient "view source" link to each Javadoc page.

Since 2011 the source code can be downloaded with the SDK Manager (Window > Android SDK Manager)

• Install package "Sources for Android SDK"
• Open Properties of android.jar, which you can find in the package explorer below the Android library
• In "Java Source Attachment", select android/sdk/sources as external folder

Edit: Eclipse seems to regularly scan the external folder for updates. If this annoys you, you can zip the folder into a .jar and then tell Eclipse to look in that jar for the sources. Eclipse will then no longer scan for changes.