Accessability of native sensors in Nativescript

Question

I am the decision of choosing to implement an app in either Nativescript (Cross platform IOS/Android) or doing a 'real' native app with java/swift accordingly.

Discarding the obvious 1 codebase vs 2 codebase discussion, I am uncertain of the limitations of Nativescript, if any.

The main concern lies in the app's heavy demand for sensor data. I have to use a lot of the phone sensors in the app. Sensors like the android sensors.

I get mostly what Nativescript does. But the question is, will chosing Nativescript impact either the accessibility of sensors or the overall performance considering the app's heavy demand for native sensor data?

I've found several plugins (like this accelerometer plugin) and I am worried I would need a plugin for each sensor and maybe there will be a missing plugin for some of the sensors. Should this be concern?

Answer 1

There will be no limitation to accessing any of the sensors. As you mentioned there is the accelerometer plugin and there are a few others. However, depending on the sensor you might have to write some of your logic to those APIs which shouldn't be too challenging if you're considering going with java/swift 😁. Here is something I've worked on recently where I needed the heart rate sensor on a WearOS app, this is not a production project at the moment, but it is planned to be released eventually.

As mentioned in the comments to the OP: You will end up using the Sensor Listener to access the data which is returned in the onSensorChanged event.

The following code is how to access the Heart Rate sensor on a device.

First, get the device Sensor Manager:

Import/require the application module from NS so you can access the Android activity in the sample below

import * as application from 'tns-core-modules/application';

  const activity: android.app.Activity =
    application.android.startActivity ||
    application.android.foregroundActivity;
  const mSensorManager = activity.getSystemService(
    android.content.Context.SENSOR_SERVICE
  ) as android.hardware.SensorManager;

Then create our listener:

const myHrListener = new android.hardware.SensorEventListener({
      onAccuracyChanged: (sensor, accuracy) => {},
      onSensorChanged: event => {
        console.log(event.values[0]);
        const HR = event.values[0].toString().split('.')[0];
        // HR is the BPM from the sensor here
      }
    });

Then we need to get the sensor:

const mHeartRateSensor = mSensorManager.getDefaultSensor(
    android.hardware.Sensor.TYPE_HEART_RATE
  );

Finally, we register the listener:

const didRegListener = mSensorManager.registerListener(
    myHrListener,
    mHeartRateSensor,
    android.hardware.SensorManager.SENSOR_DELAY_NORMAL
  );

The registerListener method returns a boolean so you can do a check if the boolean returned is true which means the listener was successful in registering and you'll get data when the sensor provides it in the onSensorChanged event.