By default, Android APPs don’t have any permissions.
Permissions involved in the APP runtime need to be declared
in the label of uses-permission in the AndroidManifest.xml of
APK file. At the time of installation, Android APP package
manager will prompt the user of the application of the APP
permissions Only with the authorization of the user, the
installation can begin, otherwise, installation will be cancelled.
After successful installation, the system will answer the
requests for program to access resources according to the
solidification permission information when APP runs. If there
are corresponding permissions, access successes; otherwise
the APP will be forced to shut down by system. The specific
process is shown in figure 1.