This version of the rendering library is more recent than your version of ADT plug-in. Please update ADT plug-in.

http://stackoverflow.com/questions/18852983/eclipse-reports-rendering-library-more-recent-than-adt-plug-in

1. Click Help > Install New Software.
2. In the Work with field, enter: https://dl-ssl.google.com/android/eclipse/
3. Select Developer Tools / Android Development Tools.
4. Click Next and complete the wizard.

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Change android version while rendering layout. Change in API version 18 to 17 work for me. -------------------------------------------------- The Reason for Warning is your using Old ADT (Android development tools), so Update your ADT by following the procedures below Procedure 1: Inside Eclipse Click Help menu Choose Check for Updates It will show Required Updates in that window choose All options using Check box or else choose ADT Updated. Procedure 2: Click Help > Install New Software. In the Work with field, enter: https://dl-ssl.google.com/android/eclipse/ Select Developer Tools / Android Development Tools. Click Next and complete the wizard.