ng-click doesn't work within the template of a directive

Madhusudhan picture Madhusudhan · May 10, 2013 · Viewed 39.1k times · Source

Angular noob here. I am creating a directive to recursively display a tree of questions and sub questions. I am using a link in the template which calls a function within the scope. For some reason, it does't call the editQuestion() method.

Here's the code and the fiddle http://jsfiddle.net/madhums/n9KNv/

HTML:

<div ng-controller="FormCtrl">
  <questions value="survey.questions"></questions>
</div>

Javascript:

var app = angular.module('myApp', []);

function FormCtrl ($scope) {
  $scope.editQuestion = function (question) {
    alert('abc');
  };
  $scope.survey = {
    // ...
  }
}


app.directive('questions', function($compile) {
  var tpl = '<ol ui-sortable' +
    ' ng-model="value"' +
    ' class="list">' +
    '  <li ng-repeat="question in value | filter:search"' +
    '     <a href="" class="question">' +
    '       {{ question.name }}' +
    '     </a>' +
    '     <span class="muted">({{ question.type }})</span>' +
    '     <a href="" class="danger" ng-click="removeQuestion(question)">remove</a>' +
    '     <a href="" class="blue" ng-click="editQuestion(question)">edit</a>' +
    '     <choices value="question.choices"></choices>' +
    '  </li>' +
    '</ol>';

  return {
    restrict: 'E',
    terminal: true,
    scope: { value: '=' },
    template: tpl,
    link: function(scope, element, attrs) {
        $compile(element.contents())(scope.$new());
    }
  };
});

app.directive('choices', function($compile) {
  var tpl = '<ul class="abc" ng-repeat="choice in value">'+
    '  <li>' +
    '    {{ choice.name }}' +
    '    <span class="muted">' +
    '      ({{ choice.questions.length }} questions)' +
    '    </span>' +
    '' +
    '    <a href=""' +
    '      ng-click="addQuestions(choice.questions)"' +
    '      tooltip="add sub questions">' +
    '      +' +
    '    </a>' +
    '' +
    '    <questions value="choice.questions"></questions>'
    '  </li>' +
    '</ul>';

  return {
    restrict: 'E',
    terminal: true,
    scope: { value: '=' },
    template: tpl,
    link: function(scope, element, attrs) {
        $compile(element.contents())(scope.$new());
    }
  };
});

Any help in understanding this would be appreciated.

Answer

Langdon picture Langdon · May 10, 2013

You've got a scope issue. Since you used isolated scope in your directive with scope: { value: '=' }, it no longer has access to your controller's scope that has editQuestion.

You need to pass editQuestion along to your directive's scope so it knows how to call it. This is typically pretty easy, but because of your infinitely recursive directive structure where choices can include questions, it gets a bit trickier. Here's a working fiddle:

http://jsfiddle.net/n9KNv/14/

The HTML now includes a reference to editQuestion:

<div ng-controller="FormCtrl">
    <questions value="survey.questions" on-edit="editQuestion(question)"></questions>
</div>

And your questions directive now expects an onEdit attribute in its scope:

app.directive('questions', function($compile) {
  var tpl = '<ol ui-sortable' +
    ' ng-model="value"' +
    ' class="list">' +
    '  <li ng-repeat="question in value | filter:search"' +
    '     <a href="" class="question">' +
    '       {{ question.name }}' +
    '     </a>' +
    '     <span class="muted">({{ question.type }})</span>' +
      '     <a href="" class="blue" ng-click="onEdit({question: question})">edit</a>' +
      '     <choices value="question.choices" on-edit="onEdit({question: subQuestion})"></choices>' +
    '  </li>' +
    '</ol>';

  return {
    restrict: 'E',
    terminal: true,
      scope: { value: '=', onEdit: '&' },
    template: tpl,
    link: function(scope, element, attrs) {
        $compile(element.contents())(scope.$new());
    }
  };
});

app.directive('choices', function($compile) {
  var tpl = '<ul class="abc" ng-repeat="choice in value">'+
    '  <li>' +
    '    {{ choice.name }}' +
    '    <span class="muted">' +
    '      ({{ choice.questions.length }} questions)' +
    '    </span>' +
    '' +
      '    <questions value="choice.questions" on-edit="onEdit({subQuestion: question})"></questions>'
    '  </li>' +
    '</ul>';

  return {
    restrict: 'E',
    terminal: true,
      scope: { value: '=', onEdit: '&' },
    template: tpl,
    link: function(scope, element, attrs) {
        $compile(element.contents())(scope.$new());
    }
  };
});

Notice how we're targeting question in the ng-click. This is how you target arguments in callback functions. Also notice how in the on-edit we're passing to your choices directive, we're targeting subQuestion. This is because question is already reserved inside of the ngRepeat, so we need to differentiate between the two.

This was probably the hardest concept for me to learn in Angular so far. Once you understand how scope works between controllers, directives, and other directives, the world of Angular is yours. :)