I\'ve previously had success attaching the Android Source to Eclipse by following Finn Johnsen\'s instructions here.
However this approach seems to have stopped work
The best way is as below.
Update Android SDK Manager, including source of the version you need.
click on Any class like activity, if source is properly attached, it will open the Activity class.
If it is not opening up, then click on the attach source and can give source path as above.
Source path will be like android-sdk-windows\sources\android-17
This will help you to add source for android SDK