React Native: how to add codes inside sensor subscribe with react-native-sensors

Question

I am using react-native-sensors for getting accelerometer readings. It is reading the sensor values correctly. Being new to React Native, I couldn't figure out how to add codes to calculate the acceleration vector inside the sensor.subscribe method.

import { 
setUpdateIntervalForType, 
SensorTypes, 
accelerometer, 
gyroscope 
} from 'react-native-sensors';

........

export default class Accelerometer extends Component {

constructor(props) {
    super(props);

    setUpdateIntervalForType(SensorTypes.accelerometer, 200);
    this.accelSubscription = accelerometer.subscribe(({ x, y, z, timestamp }) =>
        this.setState({
            accel_x: x,
            accel_y: y,
            accel_z: z,
        })
    );

    this.state = {
        acceleration: 0,
        accel_x: 0,
        accel_y: 0,
        accel_z: 0,
    };
}

And here's the calculation codes I want to perform whenever I get new accelerometer readings:

    const accelx = this.state.accel_x;
    const accely = this.state.accel_y;
    const accelz = this.state.accel_z;
    const lastAccel = this.state.acceleration;
    const currAcceleration = Math.sqrt((accelx * accelx) + (accely * accely) + (accelz * accelz));
    //I need to delta value to detect changes
    const accelerationDelta = currAcceleration - lastAccel;
    this.setState({
        acceleration: currAcceleration,
    });

If I put the codes directly inside the accelerometer.subscribe() it will throw error. How can I accomplish this?

Answer 1

You should put your code inside brackets.
In arrow function if you don't use {} then you can only write one line

accelerometer.subscribe(({ x, y, z, timestamp }) =>{
    this.setState({ accel_x: x });
    alert('Test this');
}