Java. Lang. classnotfoundexception: Didn't find Class "***** activity" on path:/Data

Many people see Java. lang. runtimeexception: Unable to instantiate activity componentinfo {***** activity}: Java. lang. classnotfoundexception: Didn't find class "***** activity"
On Path:/data/APP /*******. APK error. In Android development, I also encountered this problem. After two days of struggle, I finally solved the problem. I added the online information and provided it to you.

1. The name of the activity registered in the manifest file. Are there any mistakes in the package name? Some netizens may only write one class name, which should be replaced by the DoT number, however, this class is not in the default package, so if this error is reported, you only need to write the full name of the class.

2. For some Android systems, some third-party packages are required and can be directly introduced. It was previously possible, but not in the latest ADT. You must create a new libs folder in the program, copy a third-party jar file to the libs folder. Many people report errors because of this. In particular, this libs folder is not used by default for previous projects, but the new version of ADT, the libs folder is created by default.

3. One thing is also very important. In order and export under the Java build path panel, you must check the JAR file you introduced. Otherwise, it is the same as not referenced. Remember.

This is generally the reason for the past. If you have any questions you cannot understand or have any other reasons, please leave a message with me to share and make progress together!