Android project with red exclamation mark solution

First, look at the SDK version, usually two, the first is the target=android-in the Project.Properties file? Modify the SDK version corresponding to your project, the second is the manifest file, android:minsdkversion= "10"

android:targetsdkversion= "19" should also be modified into the corresponding SDK version of the project

Then, if after the above modification, the project still has red exclamation mark, how to do?

This is most likely due to the fact that the auto-associated jar package is inconsistent with the path of your local jar package after the project is imported.

Right-click Project->buile path->configure buid path->add external->jars Import into the project jar package file, then remove the previously Red Fork jar package