AngularJS - Create a directive that uses ng-model

angularjs directive

EDIT: This answer is old and likely out of date. Just a heads up so it doesn't lead folks astray. I no longer use Angular so I'm not in a good position to make improvements.

It's actually pretty good logic but you can simplify things a bit.

Directive

var app = angular.module('plunker', []);app.controller('MainCtrl', function($scope) {  $scope.model = { name: 'World' };  $scope.name = "Felipe";});app.directive('myDirective', function($compile) {  return {    restrict: 'AE', //attribute or element    scope: {      myDirectiveVar: '=',     //bindAttr: '='    },    template: '<div class="some">' +      '<input ng-model="myDirectiveVar"></div>',    replace: true,    //require: 'ngModel',    link: function($scope, elem, attr, ctrl) {      console.debug($scope);      //var textField = $('input', elem).attr('ng-model', 'myDirectiveVar');      // $compile(textField)($scope.$parent);    }  };});

Html with directive

<body ng-controller="MainCtrl">  This scope value <input ng-model="name">  <my-directive my-directive-var="name"></my-directive></body>

CSS

.some {  border: 1px solid #cacaca;  padding: 10px;}

You can see it in action with this Plunker.

Here's what I see:

I understand why you want to use 'ng-model' but in your case it's not necessary. ng-model is to link existing html elements with a value in the scope. Since you're creating a directive yourself you're creating a 'new' html element, so you don't need ng-model.

EDIT As mentioned by Mark in his comment, there's no reason that you can't use ng-model, just to keep with convention.

By explicitly creating a scope in your directive (an 'isolated' scope), the directive's scope cannot access the 'name' variable on the parent scope (which is why, I think, you wanted to use ng-model).
I removed ngModel from your directive and replaced it with a custom name that you can change to whatever.
The thing that makes it all still work is that '=' sign in the scope. Checkout the docs docs under the 'scope' header.

In general, your directives should use the isolated scope (which you did correctly) and use the '=' type scope if you want a value in your directive to always map to a value in the parent scope.

angularjs directive

I took a combo of all answers, and now have two ways of doing this with the ng-model attribute:

With a new scope which copies ngModel
With the same scope which does a compile on link

Show code snippet

var app = angular.module('model', []);app.controller('MainCtrl', function($scope) {  $scope.name = "Felipe";  $scope.label = "The Label";});app.directive('myDirectiveWithScope', function() {  return {    restrict: 'E',    scope: {      ngModel: '=',    },    // Notice how label isn't copied    template: '<div class="some"><label>{{label}}: <input ng-model="ngModel"></label></div>',    replace: true  };});app.directive('myDirectiveWithChildScope', function($compile) {  return {    restrict: 'E',    scope: true,    // Notice how label is visible in the scope    template: '<div class="some"><label>{{label}}: <input></label></div>',    replace: true,    link: function ($scope, element) {      // element will be the div which gets the ng-model on the original directive      var model = element.attr('ng-model');      $('input',element).attr('ng-model', model);      return $compile(element)($scope);    }  };});app.directive('myDirectiveWithoutScope', function($compile) {  return {    restrict: 'E',    template: '<div class="some"><label>{{$parent.label}}: <input></label></div>',    replace: true,    link: function ($scope, element) {      // element will be the div which gets the ng-model on the original directive      var model = element.attr('ng-model');      return $compile($('input',element).attr('ng-model', model))($scope);    }  };});app.directive('myReplacedDirectiveIsolate', function($compile) {  return {    restrict: 'E',    scope: {},    template: '<input class="some">',    replace: true  };});app.directive('myReplacedDirectiveChild', function($compile) {  return {    restrict: 'E',    scope: true,    template: '<input class="some">',    replace: true  };});app.directive('myReplacedDirective', function($compile) {  return {    restrict: 'E',    template: '<input class="some">',    replace: true  };});

.some {  border: 1px solid #cacaca;  padding: 10px;}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script><script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.0/angular.min.js"></script><div ng-app="model" ng-controller="MainCtrl">  This scope value <input ng-model="name">, label: "{{label}}"  <ul>    <li>With new isolate scope (label from parent):      <my-directive-with-scope ng-model="name"></my-directive-with-scope>    </li>    <li>With new child scope:      <my-directive-with-child-scope ng-model="name"></my-directive-with-child-scope>    </li>    <li>Same scope:      <my-directive-without-scope ng-model="name"></my-directive-without-scope>    </li>    <li>Replaced element, isolate scope:      <my-replaced-directive-isolate ng-model="name"></my-replaced-directive-isolate>    </li>    <li>Replaced element, child scope:      <my-replaced-directive-child ng-model="name"></my-replaced-directive-child>    </li>    <li>Replaced element, same scope:      <my-replaced-directive ng-model="name"></my-replaced-directive>    </li>  </ul>  <p>Try typing in the child scope ones, they copy the value into the child scope which breaks the link with the parent scope.  <p>Also notice how removing jQuery makes it so only the new-isolate-scope version works.  <p>Finally, note that the replace+isolate scope only works in AngularJS >=1.2.0</div>

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