Android M permission of the tested READ_PHONE_STATE(dangerous permissions)

Question

If the device is running Android 6.0 or higher when im trying to get phone number using getLine1Number():

java.lang.SecurityException: Requires

Answer 1

public class MainActivity extends AppCompatActivity {

    TextView textView;
    String device_unique_id,IMEI;


    private static final int MY_PERMISSIONS_REQUEST_READ_PHONE_STATE = 0;


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

        textView = (TextView)findViewById(R.id.textView);
    }
    public void GetImei(View view)
    {



        loadIMEI();

    }

    public void loadIMEI() {
        // Check if the READ_PHONE_STATE permission is already available.
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_PHONE_STATE)
                != PackageManager.PERMISSION_GRANTED) {
            if (ActivityCompat.shouldShowRequestPermissionRationale(this,
                    Manifest.permission.READ_PHONE_STATE)) {
//                get_imei_data();
            } else {
                ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_PHONE_STATE},
                        MY_PERMISSIONS_REQUEST_READ_PHONE_STATE);
            }
        } else {

            TelephonyManager mngr = (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
            IMEI = mngr.getDeviceId();
            device_unique_id = Settings.Secure.getString(this.getContentResolver(),
                    Settings.Secure.ANDROID_ID);
            textView.setText(device_unique_id+"----"+mngr.getDeviceId());
            // READ_PHONE_STATE permission is already been granted.
            Toast.makeText(this,"Alredy granted",Toast.LENGTH_SHORT).show();
        }
    }
       @Override
    public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions,@NonNull int[] grantResults) {

        if (requestCode == MY_PERMISSIONS_REQUEST_READ_PHONE_STATE) {

            if (grantResults.length == 1 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {

//                Toast.makeText(this,"Alredy DONE",Toast.LENGTH_SHORT).show();
                TelephonyManager mngr = (TelephonyManager)getSystemService(Context.TELEPHONY_SERVICE);
                IMEI = mngr.getDeviceId();
                device_unique_id = Settings.Secure.getString(this.getContentResolver(),Settings.Secure.ANDROID_ID);
                textView.setText(device_unique_id+"----"+mngr.getDeviceId());

            } else {
                Toast.makeText(this,"ehgehfg",Toast.LENGTH_SHORT).show();
            }
        }
    }