How to make ionic native Diagnostic checkLocation isEnabled() to work through all time in my app?

I need to make checking for GPS location all the time while the app is started and if it’s FALSE to exit an app?

import { Diagnostic } from '@ionic-native/diagnostic/ngx';
checkLocation() {

    let p = this.diagnostic.isLocationAvailable();
    p.then(function (available) {
      alert("Location is " + (available ? "available" : "not available"));
    }).catch(function (error) {
      alert("The following error occurred: " + error);
    });


  }

I’ve set Diagnostic in my app.module.ts as Provider.

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Source Url How to make ionic native Diagnostic checkLocation isEnabled() to work through all time in my app?