<!DOCTYPE html>
<html>

  <head>
    <base href="." />
    <script type="text/javascript" charset="utf-8">
      window.AngularVersionForThisPlunker = 'latest'
    </script>
    <title>angular playground</title>
    <link rel="stylesheet" href="style.css" />
    <script src="https://unpkg.com/core-js@2.4.1/client/shim.min.js"></script>
    <script src="https://unpkg.com/zone.js/dist/zone.js"></script>
    <script src="https://unpkg.com/zone.js/dist/long-stack-trace-zone.js"></script>
    <script src="https://unpkg.com/reflect-metadata@0.1.3/Reflect.js"></script>
    <script src="https://unpkg.com/systemjs@0.19.31/dist/system.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 */

.my-form {
  border: 1px solid grey;
  padding: 10px;
  background-color: darkcyan;
}

.my-input-component {
    border: 1px solid grey;
    padding: 5px;
    margin: 10px;
    background-color: lightgrey;
}

h2 { margin: 0; }
### Angular: ControlValueAccessor with reactive forms
This example helps to understand how the ControlValueAccessor works together
with a reactive form.
var angularVersion;
if(window.AngularVersionForThisPlunker === 'latest'){
  angularVersion = ''; //picks up latest
}
else {
  angularVersion = '@' + window.AngularVersionForThisPlunker;
}

System.config({
  //use typescript for compilation
  transpiler: 'typescript',
  //typescript compiler options
  typescriptOptions: {
    emitDecoratorMetadata: true
  },
  paths: {
    'npm:': 'https://unpkg.com/'
  },
  //map tells the System loader where to look for things
  map: {
    
    'app': './src',
    '@angular/core': 'npm:@angular/core'+ angularVersion + '/bundles/core.umd.js',
    '@angular/common': 'npm:@angular/common' + angularVersion + '/bundles/common.umd.js',
    '@angular/compiler': 'npm:@angular/compiler' + angularVersion  + '/bundles/compiler.umd.js',
    '@angular/platform-browser': 'npm:@angular/platform-browser' + angularVersion + '/bundles/platform-browser.umd.js',
    '@angular/platform-browser-dynamic': 'npm:@angular/platform-browser-dynamic' + angularVersion + '/bundles/platform-browser-dynamic.umd.js',
    '@angular/http': 'npm:@angular/http' + angularVersion + '/bundles/http.umd.js',
    '@angular/router': 'npm:@angular/router' + angularVersion +'/bundles/router.umd.js',
    '@angular/forms': 'npm:@angular/forms' + angularVersion + '/bundles/forms.umd.js',
    '@angular/animations': 'npm:@angular/animations' + angularVersion + '/bundles/animations.umd.js',
    '@angular/platform-browser/animations': 'npm:@angular/platform-browser' + angularVersion + '/bundles/platform-browser-animations.umd.js',
    '@angular/animations/browser': 'npm:@angular/animations' + angularVersion + '/bundles/animations-browser.umd.js',
    
    '@angular/core/testing': 'npm:@angular/core' + angularVersion + '/bundles/core-testing.umd.js',
    '@angular/common/testing': 'npm:@angular/common' + angularVersion + '/bundles/common-testing.umd.js',
    '@angular/compiler/testing': 'npm:@angular/compiler' + angularVersion + '/bundles/compiler-testing.umd.js',
    '@angular/platform-browser/testing': 'npm:@angular/platform-browser' + angularVersion + '/bundles/platform-browser-testing.umd.js',
    '@angular/platform-browser-dynamic/testing': 'npm:@angular/platform-browser-dynamic' + angularVersion + '/bundles/platform-browser-dynamic-testing.umd.js',
    '@angular/http/testing': 'npm:@angular/http' + angularVersion + '/bundles/http-testing.umd.js',
    '@angular/router/testing': 'npm:@angular/router' + angularVersion + '/bundles/router-testing.umd.js',
    'tslib': 'npm:tslib@1.6.1',
    'rxjs': 'npm:rxjs',
    'typescript': 'npm:typescript@2.2.1/lib/typescript.js'
  },
  //packages defines our app package
  packages: {
    app: {
      main: './main.ts',
      defaultExtension: 'ts'
    },
    rxjs: {
      defaultExtension: 'js'
    }
  }
});
//main entry point
import {platformBrowserDynamic} from '@angular/platform-browser-dynamic';
import {AppModule} from './app';

platformBrowserDynamic().bootstrapModule(AppModule)
//our root app component
import {Component, NgModule, VERSION, ViewChild} from '@angular/core'
import { BrowserModule } from '@angular/platform-browser';
import { ReactiveFormsModule, FormGroup, FormControl } from '@angular/forms';
import { HttpModule } from '@angular/http';

import { AppComponent } from './app.component';
import { MyInputComponent } from './my-input.component';
import { OnInit } from '@angular/core';

@Component({
  selector: 'my-app',
  template: `
    <h1>
      {{name}}
    </h1>
    <div class="my-form">
      <h2>outer form component</h2>
    
      <ul>
        <li>dirty: {{myForm.dirty}}</li>
        <li>pristine: {{myForm.pristine}}</li>
        <li>valid: {{myForm.valid}}</li>
        <li>value: {{theValue}}</li>
      </ul>
    
      <form [formGroup]="myForm">
        <app-my-input formControlName="valueName"></app-my-input>
      </form>
      
      <pre>myForm: {{ myForm.value | json}}</pre> 
    
      <div>
        <button (click)="changeThat()">change from outside</button>
        <button (click)="resetForm()">reset</button>
        <button (click)="markPristine()">markPristine</button>
      </div>  
    </div>
  `,
})
export class App {
  name:string;
  
  myForm: FormGroup;

  theValue = 'initial';

  constructor() {
    this.name = `Angular! v${VERSION.full}`;
    this.myForm = new FormGroup({ 
      // set the model value as initial value of the control
      valueName: new FormControl(this.theValue);
    });
  }
  
  ngOnInit(): void { 
    // listen to the changes in the FormGroup and copy the value
    // of the control back to the model
    this.myForm.valueChanges.subscribe(value => this.theValue = value['valueName']); 
  }

  changeThat() {
    // some code from outside changes the value of the control
    // writeValue is called
    this.myForm.setValue({valueName: 'change from outside'});
  }
  
  resetForm() {
    // resets the state of the FormGroup to pristine and valid
    // and sets the given value as initial value
    this.myForm.reset({valueName: 'initial after reset'});
  }
  
  markPristine() {
    // sets the pristine attribute of the control to true
    // does not touch the other attributes (valid, value, touched, ...)
    this.myForm.get('valueName').markAsPristine();    
  }
}

@NgModule({
  imports: [ BrowserModule, ReactiveFormsModule, HttpModule ],
  declarations: [ App, MyInputComponent ],
  bootstrap: [ App ]
})
export class AppModule {}
import {Component, forwardRef} from '@angular/core';
import {ControlValueAccessor, NG_VALUE_ACCESSOR} from '@angular/forms';

@Component({
  selector: 'app-my-input',
  template: `
    <div class="my-input-component">
      <h2>inner input component</h2>
      <div>inner value: {{myValue}}</div>
      <button (click)="changeMe()">change from inside</button>
      <button (click)="propagateInitial()">propagate initial</button>
      <button (click)="propagateSomethingValue()">propagate some value</button>
    </div>
  `,
  providers: [
    {
      provide: NG_VALUE_ACCESSOR,
      useExisting: forwardRef(() => MyInputComponent),
      multi: true
    }
  ]
})
export class MyInputComponent implements ControlValueAccessor {

  myValue: any = null;
  propagateChange = (_: any) => {};

  constructor() { }

  writeValue(obj: any): void {
    console.log('writeValue', obj);
    this.myValue = obj;
    //this.propagateChange(this.myValue);
  }

  registerOnChange(fn: any): void {
    this.propagateChange = fn;
  }

  registerOnTouched(fn: any): void {
    // do nothing
  }


  setDisabledState(isDisabled: boolean): void {
    // do nothing
  }


  changeMe() {
    this.myValue = 'new value changed from inside';
    this.propagateChange(this.myValue);
  }
  
  propagateInitial() {
    this.propagateChange('initial');
  }
  
  propagateSomethingValue() {
    this.propagateChange('some other value');    
  }
  
}