Android 6 runtime permission for accessing gallery

Question

I got questions about Android 6 (Marshmallow) runtime permission. If user wants to pick a photo from gallery, should we ask for READ_EXTERNAL_STORAGE permission?

Seems like I could access the gallery even though I turn off the Storage permission.

Answer 1

You need to ask for READ_EXTERNAL_STORAGE. You will be able to access the gallery without it, but if you want to do anything with the media you get from the gallery you will need the READ permission.

A quick test on what happens in onActivityResult after an image has been picked form the gallery:

Permission Denial: reading com.android.providers.media.MediaProvider uri content://media/external/images/media from pid=8405, uid=10177 requires android.permission.READ_EXTERNAL_STORAGE, or grantUriPermission()

Answer 2

For custom permission,you may use runtime permission if you are using Android 6.0 or above.This code may help you .

If your app doesn't already have the permission it needs, the app must call one of the requestPermissions() methods to request the appropriate permissions. Your app passes the permissions it wants, and also an integer request code that you specify to identify this permission request. This method functions asynchronously: it returns right away, and after the user responds to the dialog box, the system calls the app's callback method with the results, passing the same request code that the app passed to requestPermissions().

// Here, thisActivity is the current activity
if (ContextCompat.checkSelfPermission(thisActivity,
                Manifest.permission.READ_CONTACTS)
        != PackageManager.PERMISSION_GRANTED) {

    // Should we show an explanation?
    if (ActivityCompat.shouldShowRequestPermissionRationale(thisActivity,
            Manifest.permission.READ_CONTACTS)) {

        // Show an explanation to the user *asynchronously* -- don't block
        // this thread waiting for the user's response! After the user
        // sees the explanation, try again to request the permission.

    } else {

        // No explanation needed, we can request the permission.

        ActivityCompat.requestPermissions(thisActivity,
                new String[]{Manifest.permission.READ_CONTACTS},
                MY_PERMISSIONS_REQUEST_READ_CONTACTS);

        // MY_PERMISSIONS_REQUEST_READ_CONTACTS is an
        // app-defined int constant. The callback method gets the
        // result of the request.
    }
}    

To Know more about runtime permission

https://developer.android.com/training/permissions/requesting.html