[Android] Context

1. Docs
2. Important methods
   
   • Activity
     start
     
   • Service
     bind/unbind, start/stop, getSystemService
     
   • BroadcastReceiver
     register/unregister, send
     
   • ContentProvider
     getContentResolver
     
   • Resources
     
     • getResources
       
     • getPackageResourcePath
     • getString
     • getText
     • xxx
       
   • Theme
     
     • setTheme/getTheme
     • obtainStyledAttributes
       
   • Database
     list/delete (databaseList/deleteDatabase), openOrCreateDatabase
     
   • File
     list/delete (fileList/deleteFile), openFileInput/openFileOutput
     
   • Directory
     
     • getDir
     • getExternalFilesDir
       
     • getCacheDir
     • getExternalCacheDir
     • getFileStreamPath
       
     • getDatabasePath
     • getFilesDir
     • getPackageCodePath
       
   • Permission
     check/enforce permission or permission on uri, grant permission on uri.
     
   • Others
     
     • createPackageContext
       Return a new Context object for the given application name.
     • getApplicationContext
       
     • getApplicationInfo
       
     • getAssets
       
     • getClassLoader
       
     • getMainLooper
     • getPackageManager
     • getPackageName
     • getSharedPreferences
       
     • xxx
       
   • xxx
     
3. xxx