1.SDK version does not correspond, you can open the Project.Properties file in your project, modify target=android-18 (I This is 18), change 18 to 14 (others can), and then change back to 18 will reload.
2.V4 package does not correspond, re-import the V4 package of your current environment 3. If you reference the project type lib, right-click on the project-->properties-->Android---see if the item was introduced, check if the IS library 4.styles.xml file error, may have used a higher version of the style, download the high version or change the style to the lower version 5. If the encoding causes a program error, see if the error code contains garbled characters 6. Because of the error caused by the jar package, right-click Project-->bulid path-->cfg Bulid Path to check if the jar package is an error, re-Add. 7. You can also clean project, fix project
Android Eclipse Project Import Common errors
