App Permissions
Codelab
Who am I?!
Deuphil Kaufmann
@deubaka
SDK Developer @ HyperGrowth
PADC Co-organizer
Java/Android/Mobile
Prerequisite
-
Build tools at least 23.x.x
-
Support library at least 23.x.x
-
Android 6.0 Emulator/Device
Permissions - then and now
But why?
- Permissions were out of context and vague
- Users will tap it anyway
- Created friction during installs/updates
- All or nothing
- No post installation user control
Which in what?
- 8 Permission Group
- Contacts
- Calendar
- SMS
- Location
- Camera
- Sensors
- Microphone
- 2 Protection Categories
- Normal - Enabled by default on install time
- ACCESS_NETWORK_STATE
- INTERNET
- BLUETOOTH
- Dangerous - Must request on runtime
When and how to ask?
How to?
-
Check for permission before executing affected code
- Use ContextCompat-subclasses to access checkSelfPermissions
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA)
== PackageManager.PERMISSION_GRANTED) {
// Do code here
} else {
// Request permission here
}
- Use ActivityCompat.requestPermissions() to request permissions
if (ActivityCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.CAMERA) {
Snackbar.make(mAnchorLayout, "Camera permission is needed to attach pictures",
Snackbar.LENGTH_INDEFINITE)
.setAction(R.string.ok, new View.OnClickListener() {
@Override
public void onClick(View view) {
ActivityCompat.requestPermissions(MainActivity.this,
new String[]{Manifest.permission.CAMERA}, REQUEST_CAMERA);
}
})
.show();
} else {
ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA},
REQUEST_CAMERA);
}
...
- Implement ActivityCompat.OnRequestPermissionsResultCallback
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,
@NonNull int[] grantResults) {
if (requestCode == REQUEST_CAMERA) {
if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { Snackbar.make(mAnchorLayout, "You can now take photos",
Snackbar.LENGTH_SHORT).show();
} else { Snackbar.make(mAnchorLayout, "Permission not granted",
Snackbar.LENGTH_SHORT).show();
}
}
}
Gotchas
- If device is API 22/Lollipop and below OR targetSdk is 22 and below, then permissions will be granted at install time
- If device is API 23/Marshmallow and above AND targetSdk is 23 and above, then permissions can be denied and are runtime
- If device is API 23/Marshmallow BUT targetSdk is 22 and below, then permissions can still be denied, but won't crash
- Once "Never ask again" is ticked, ActivityCompat.shouldShowRequestPermissionRationale will always return false
- Option to redirect to app info page only
Some things to keep in mind
- You still need to define all your app's permission in your AndroidManifest.xml
-
Consider using an intent to offload the permission request, ex. launch camera app instead
- Only ask when you need it (see quadrant)
- Be mindful not to overwhelm user
- Explain why you need it (see quadrant again)
- By providing runtime permissions on your app, you create a "trust" between your product and user
End
References and further readings
DevFest 2015 - Android 6.0 App Permissions
By Deuphil Kaufmann (deu)
DevFest 2015 - Android 6.0 App Permissions
A presentation/codelab on Android 6.0 Marshmallow new App Permissions for GDG DevFest 2015 held at PLDT InnoLab on October 16-17, 2015.
