android - Do I have to declare both WRITE_EXTERNAL_STORAGE and READ_EXTERNAL_STORAGE?

Question

Is it enough to declare <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" /> or do I also have to declare <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />? The Javadocs omit this important information.

Answer 1

It's best to be explicit and declare both permissions, but declaring only android.permission.WRITE_EXTERNAL_STORAGE will automatically add android.permission.READ_EXTERNAL_STORAGE to your APK at build time.

You can use the command aapt dump badging on an APK to see that Android considers usage of the write permission to imply that you also want read permission.

Here's some output from aapt for an APK of mine where I declared only WRITE_EXTERNAL_STORAGE in my manifest:

uses-permission:'android.permission.WRITE_EXTERNAL_STORAGE'
uses-permission:'android.permission.READ_EXTERNAL_STORAGE'
uses-implied-permission:'android.permission.READ_EXTERNAL_STORAGE',
  'requested WRITE_EXTERNAL_STORAGE'