home.ts

import { Platform } from 'ionic-angular';
import { BackgroundMode } from '@ionic-native/background-mode';
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export class HomePage {

  constructor(public backgroundMode: BackgroundMode, public platform: Platform) {

    platform.ready().then(() => {
    
      this.backgroundMode.on('activate').subscribe(() => {
        console.log('activated');
      });
      
      this.backgroundMode.enable();
    })
  }
}