How to get OneSignal Push Notification Device ID Ionic 3 - ionic-framework

Question

I have implemented the push notification functionality in my ionic app but it is not working. I am not getting the register id after the app is deployed. Following is my code.
app.component.ts
constructor(public platform: Platform, public splashScreen: SplashScreen, public menu: MenuController,
private storage: StorageService,private toast: ToastService, public events: Events, private push: Push,
private alertCtrl: AlertController, public network: Network, private api: UserService) {
platform.ready().then(() => {
debugger
this.pushSetup();
this.userDetails = this.storage.getData('userDetails');
this.isAlertShown = false;
// this.task = setInterval(() => {
// this.checkInternet();
// }, 3000);
if (this.userDetails != undefined || this.userDetails != null) {
this.rootPage = 'welcome';
} else {
this.rootPage = 'login';
}
this.initializeApp();
});
pushSetup() {
console.log("inside pushSetup");
const options: PushOptions = {
android: {
senderID: '592660866764',
forceShow: 'true'
},
ios: {
alert: 'true',
badge: true,
sound: 'false'
}
};
console.log("inside pushSetup 1");
const pushObject: PushObject = this.push.init(options);
pushObject.on('notification').subscribe((notification: any) => console.log('Received a notification', notification));
pushObject.on('registration').subscribe((registration: any) =>console.log('Received a notification', registration));
pushObject.on('error').subscribe(error => console.error('Error with Push plugin', error));
}

Answer 1

Install the Cordova and Ionic Native plugins:
ionic cordova plugin add onesignal-cordova-plugin
npm install --save #ionic-native/onesignal
insert in app.module.ts Onesignal
import { OneSignal } from '#ionic-native/onesignal';
providers: [
....
OneSignal
...
]
In App Component you needs One Signal App ID and Google Project ID
in app.component.ts:
import { OneSignal } from '#ionic-native/onesignal';
import { Platform } from 'ionic-angular';
constructor(public oneSignal: OneSignal,
private platform: Platform) { }
onseSignalAppId: string = 'YOUR_ONESIGNAL_APP_ID';
googleProjectId: string = 'YOUR_GOOGLE_PROJECT_ID';
if(this.platform.is('cordova')) {
if (this.platform.is('android')) {
this.oneSignal.startInit(this.onseSignalAppId, this.googleProjectId);
}
else if (this.platform.is('ios')) {
this.oneSignal.startInit(this.onseSignalAppId);
}
this.oneSignal.inFocusDisplaying(this.oneSignal.OSInFocusDisplayOption.Notification);
this.oneSignal.handleNotificationReceived().subscribe(() => {
// do something when notification is received
});
this.oneSignal.handleNotificationOpened().subscribe(result => {
// do something when a notification is opened
});
this.oneSignal.endInit();
// AND THIS METHOD RETURN YOUR DEVICES USER_ID
this.oneSignal.getIds().then(identity => {
alert(identity.pushToken + ' it's PUSHTOKEN');
alert(identity.userId + 'it's USERID);
});
}