Angular2 + select ControlValueAccessor implementation

<!DOCTYPE html>
<html>

  <head>
    <title>angular2 playground</title>
    <link rel="stylesheet" href="style.css" />
    <script src="https://code.angularjs.org/2.0.0-beta.17/angular2-polyfills.js"></script>
    <script src="https://code.angularjs.org/tools/system.js"></script>
    <script src="https://code.angularjs.org/tools/typescript.js"></script>
    <script src="config.js"></script>
    <script>
    System.import('app')
      .catch(console.error.bind(console));
  </script>
  </head>

  <body>
    <my-app>
    loading...
  </my-app>
  </body>

</html>

/* Styles go here */

### Angular2 Starter Plunker - Typescript - RC.0

A simple plunker demonstrating Angular2 usage:
- Uses SystemJS + TypeScript to compile on the fly
- Includes binding, directives, http, pipes, and DI usage.

System.config({
  //use typescript for compilation
  transpiler: 'typescript',
  //typescript compiler options
  typescriptOptions: {
    emitDecoratorMetadata: true
  },
  //map tells the System loader where to look for things
  map: {
    app: "./src",
    '@angular': 'https://npmcdn.com/@angular',
    'rxjs': 'https://npmcdn.com/rxjs@5.0.0-beta.6'
  },
  //packages defines our app package
  packages: {
    app: {
      main: './main.ts',
      defaultExtension: 'ts'
    },
    '@angular/core': {
      main: 'bundles/core.umd.js',
      defaultExtension: 'js'
    },
    '@angular/http': {
      main: 'index.js',
      defaultExtension: 'js'
    },
    '@angular/compiler': {
      main: 'bundles/compiler.umd.js',
      defaultExtension: 'js'
    },
    '@angular/common': {
      main: 'bundles/common.umd.js',
      defaultExtension: 'js'
    },
    '@angular/platform-browser-dynamic': {
      main: 'bundles/platform-browser-dynamic.umd.js',
      defaultExtension: 'js'
    },
    '@angular/platform-browser': {
      main: 'bundles/platform-browser.umd.js',
      defaultExtension: 'js'
    },
    rxjs: {
      defaultExtension: 'js'
    }
  }
});

//main entry point
import { bootstrap } from '@angular/platform-browser-dynamic';
import { HTTP_PROVIDERS } from '@angular/http';

import { App } from './app';

bootstrap(App, [HTTP_PROVIDERS])
  .catch(err => console.error(err));

//our root app component
import { Component } from '@angular/core';

import { EnvironmentSelectorComponent } from './environment-selector.component';
import { EnvironmentService } from './environment.service';


@Component({
  selector: 'my-app',
  template: `<h1>Angular 2 Systemjs start</h1>
    {{selectedEnvironment | json}}
    <environment [(ngModel)]="selectedEnvironment" [useForm]="false"></environment>
  `,
  providers: [EnvironmentService],
  directives: [EnvironmentSelectorComponent]
})
export class App {
  selectedEnvironment = {
    "id": "2",
    "name": "environment2"
  };
}

[{
  "id": "2",
  "name": "environment2"
},{
  "id": "3",
  "name": "environment3"
},{
  "id": "4",
  "name": "environment4"
}]

import { Injectable } from '@angular/core';
import { Http } from '@angular/http';

import 'rxjs/add/operator/map';

@Injectable()
export class EnvironmentService {
  constructor(private http: Http) {}

  getEnvironments() {
    return this.http.get('src/environments.json')
      .map(res => res.json());
  }
}

import { Component, Input, Output, OnInit, EventEmitter, Provider, forwardRef } from '@angular/core';
import { NG_VALUE_ACCESSOR, ControlValueAccessor } from '@angular/common';
import { Environment } from './environment';
import { EnvironmentService } from './environment.service';

const SELECTOR_VALUE_ACCESSOR: Provider = new Provider(NG_VALUE_ACCESSOR, {
    useExisting: forwardRef(() => EnvironmentSelectorComponent),
    multi: true
});

@Component({
  selector: 'environment',
  providers: [SELECTOR_VALUE_ACCESSOR],
  template: `
    <select [(ngModel)]="selectedEnvironment" (ngModelChange)="onChange($event)"
      [ngClass]="{'form-control': useForm}"
      class="custom-select">
      <option [ngValue]="i" *ngFor="let i of environments">{{i.name}}</option>
    </select>`
})
export class EnvironmentSelectorComponent implements OnInit, ControlValueAccessor {  
    isLoading = true;
    staging: Environment = {
        id: '1',
        name: 'staging' 
    };

    selectedId: any;
    selectedEnvironment: Environment;

    @Input() useForm = false;

    @Output() ngModelChange = new EventEmitter();

    onChange(newValue:any) {
        this.ngModelChange.emit(this.selectedEnvironment)
    }

    environments = [this.staging];

    constructor(private environmentService: EnvironmentService) { }

    ngOnInit(){
        this.environmentService.getEnvironments()
            .subscribe(environments => {
                for (var i = 0; environments.length > i; i++) { 
                    this.environments.push(environments[i])
                }

                this.selectedEnvironment = this.environments.find(x => x.id === this.selectedId);
            },
            null,
            () => { this.isLoading = false; });
    } 

    onModelChange: Function = () => {};
    
    onModelTouched: Function = () => {};

    writeValue(model: Environment) : void {
        if(!model) return;
        this.selectedId = model.id;
    }
    
    registerOnChange(fn: Function): void {
        this.onModelChange = fn;
    }

    registerOnTouched(fn: Function): void {
        this.onModelTouched = fn;
    }
}

export interface Environment {
  id: string,
  name: string
}