AngularJS custom form component / directive using ng-model

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Implementing custom form controls (using ngModel)

Use the ngModel controller and the object form of the require property in the DDO:

angular.module('myModule', [])
.directive('myDirective', function() {
  return {
    restrict: 'E',
    require: { ngModelCtrl: 'ngModel' },
    scope: {
      ngModel: '<'
    },
    bindToController: true,
    controllerAs: '$ctrl',
    template: 
       `<div>
          <button ng-click="$ctrl.ngModelCtrl.$setViewValue('foo')">
              Set foo
          </button>
          <button ng-click="$ctrl.ngModelCtrl.$setViewValue('bar')">
              Set bar
          </button>
       </div>`,
    controller: function ctrl() {}
  };
});

Usage:

<form name="myForm">
    <input type="text" ng-model="foobar">
    <my-directive ng-model="foobar"></my-directive>
</form>

By instantiating and using the ng-model controller, the directive will automatically set the form controls as necessary.

The DEMO

angular.module('myModule', [])
.directive('myDirective', function() {
  return {
    restrict: 'E',
    require: { ngModelCtrl: 'ngModel' },
    scope: {
      ngModel: '<'
    },
    bindToController: true,
    controllerAs: '$ctrl',
    template: 
       `<div>
          <button ng-click="$ctrl.ngModelCtrl.$setViewValue('foo')">
              Set foo
          </button>
          <button ng-click="$ctrl.ngModelCtrl.$setViewValue('bar')">
              Set bar
          </button>
       </div>`,
    controller: function ctrl() {}
  };
});
<script src="https://unpkg.com/angular/angular.js"></script>
  <body ng-app="myModule">
    <h2>ngModel DEMO</h2>
    <form name="myForm">
        <input type="text" ng-model="foobar">
        <my-directive ng-model="foobar"></my-directive>
    </form>
    <br>myForm.$dirty = {{myForm.$dirty}}
    <br>myForm.$pristine = {{myForm.$pristine}}
    <br><button ng-click="myForm.$setDirty()">Set dirty</button>
    <br><button ng-click="myForm.$setPristine()">Set pristine</button>
  </body>

I recommend isolate scope with ngModel as an input. Output should be done with the $setViewValue method.

For more information, see

  • AngularJS Developer Guide – Implementing custom form controls (using ngModel)

  • AngularJS Developer Guide – Component-based application architecture

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