PermissionControlActivity.java

@RuntimePermissions
public class PermissionControlActivity extends AppCompatActivity {

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_permissions);

        checkPermissions();
    }

    private void checkPermissions() {
        PermissionControlActivityPermissionsDispatcher.canGoWithCheck(this);
    }

    @NeedsPermission({Manifest.permission.READ_CONTACTS, Manifest.permission.CAMERA,
            Manifest.permission.ACCESS_FINE_LOCATION,
            Manifest.permission.READ_PHONE_STATE,
            Manifest.permission.WRITE_EXTERNAL_STORAGE})
    void canGo() {
        //Permissions ok, go to next flow step.
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        PermissionControlActivityPermissionsDispatcher.onRequestPermissionsResult(this, requestCode, grantResults);
    }

    @OnShowRationale(Manifest.permission.READ_CONTACTS)
    void showContactsPermissionRequest(final PermissionRequest request) {
        showRationaleDialog(R.string.request_permission_contacts, request);
    }

    @OnShowRationale(Manifest.permission.CAMERA)
    void showCameraPermissionRequest(final PermissionRequest request) {
        showRationaleDialog(R.string.request_permission_camera, request);
    }

    @OnShowRationale(Manifest.permission.ACCESS_FINE_LOCATION)
    void showLocationPermissionRequest(final PermissionRequest request) {
        showRationaleDialog(R.string.request_permission_location, request);
    }

    @OnShowRationale(Manifest.permission.READ_PHONE_STATE)
    void showPhoneStatePermissionRequest(final PermissionRequest request) {
        showRationaleDialog(R.string.request_permission_phone_state, request);
    }

    @OnShowRationale(Manifest.permission.WRITE_EXTERNAL_STORAGE)
    void showStoragePermissionRequest(final PermissionRequest request) {
        showRationaleDialog(R.string.request_permission_storage, request);
    }

    //Denied
    @OnPermissionDenied(Manifest.permission.READ_CONTACTS)
    void showDeniedForContacts() {
    }

    @OnPermissionDenied(Manifest.permission.CAMERA)
    void showDeniedForCamera() {
    }

    @OnPermissionDenied(Manifest.permission.ACCESS_FINE_LOCATION)
    void showDeniedForLocation() {
    }

    @OnPermissionDenied(Manifest.permission.READ_PHONE_STATE)
    void showDeniedForPhoneState() {
    }

    @OnPermissionDenied(Manifest.permission.WRITE_EXTERNAL_STORAGE)
    void showDeniedForStorage() {
    }

    //Never Ask Again
    @OnNeverAskAgain(Manifest.permission.CAMERA)
    void showNeverAskForPermissions() {
    }

    private void showRationaleDialog(@StringRes int messageResId, final PermissionRequest request) {
        new AlertDialog.Builder(this)
                .setPositiveButton(R.string.button_allow, (dialog, which) -> request.proceed())
                .setNegativeButton(R.string.button_deny, (dialog, which) -> request.cancel())
                .setCancelable(false)
                .setMessage(messageResId)
                .show();
    }
}