Why the jar files under the Libs folder are not actively placed under the Android Private Libraries folder

In short: The problem is that the jar package is repeatedly conflicting!

At the beginning of this question I came up with a "self-righteous" answer, in the Android Private Libraries folder is packaged into the project executable, but not self-compiled because the Libs the following jar file is too large, But apparently in the execution of the time, the direct error--class not found!

So obviously that's not the problem!

Actually, it is. There is a android-support-v4.jar below the Libs folder. And suppose that you have introduced other libraries in project

If there is android-support-v4.jar in this project, then the problem arises. The V4jar package under the current project's Libs V4jar package with the included Libraryproject Libs is repeated. At this point in time, project does not place any jar packages below Libs into its own actively generated Android Private Libraries folder, and this folder will not be generated.

Workaround: Delete the Android-support-v4.jar from the current project to be able. Then Clean,build. It's OK.

Why the jar files under the Libs folder are not actively placed under the Android Private Libraries folder