Android Studio doesn\'t redirect me to API sources correctly. When I hit any function it decompiles .class file bytecode instead of accessing the right file from sdk/sources
As qbeck mentioned in his comment, resetting the path to the SDK fixed the issue for some of us.
Solution:
Android Studio 2.1 reporting in: solved the issue by resetting SDK.
Preferences -> Appearance & Behavior -> System Settings -> Android SDK.
Click on Edit to the right of Android SDK location. Next, next, next to complete the wizard and voila!