ionic geolocation plugin error: "No provider for Geolocation"

I'm trying to use geolocation in my ionic2 hello world project, and I add the ionic plugin "Geolocation" following the instruction on the official site.

I've run these two commands:

$ ionic plugin add cordova-plugin-geolocation
$ npm install --save @ionic-native/geolocation

And this is my home.ts:

import { Component } from '@angular/core';
import {Geolocation} from '@ionic-native/geolocation'
import { NavController } from 'ionic-angular';

@Component({
  selector: 'page-home',
  templateUrl: 'home.html'
})
export class HomePage {
  map:any=null;
  geoInfo:any={
      resp:'',
      data:''
  };

  constructor(
      public navCtrl: NavController,
      private geolocation: Geolocation
  ) {

  }
  
  test(){
      this.geolocation.getCurrentPosition().then((resp) => {
          this.geoInfo.resp=JSON.stringify(resp);
          // resp.coords.latitude
          // resp.coords.longitude
      }).catch((error) => {
          console.log('Error getting location', error);
          this.geoInfo.resp='Error getting location';
      });

      let watch = this.geolocation.watchPosition();
      watch.subscribe((data) => {
          this.geoInfo.data=JSON.stringify(data);
          // data can be a set of coordinates, or an error (if an error occurred).
          // data.coords.latitude
          // data.coords.longitude
      });

  }

}

However, I got the following error in my chrome's console:

EXCEPTION: Error in ./TabsPage class TabsPage - inline template:0:0 caused by: No provider for Geolocation!
error_handler.js:56ORIGINAL EXCEPTION: No provider for Geolocation!

At first I thought it was because I was debugging in browser, but then I got then same error in my Android phone.

So what does No provider for Geolocation mean and how should I use geolocation in my ionic2 project?

You need to add the provider to the NgModule, i.e module.ts under providers,

providers: [
  Geolocation
]