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JavaScript AngularJS Extending Inputs Extending Inputs: Optional require

derekdekalb
derekdekalb
15,072 Points

Link function conditional statement

I don't understand why this isn't working.... Help is very much appreciated. Thanks in advance.

app.js
angular.module('treehouseCourse', [])
  .directive('sometimesTwoWay', function() {
    return {
      // YOUR CODE HERE
      require: '?ngModel', 
      link: function($scope, $element, $attrs, ngModelCtrl){
        var isInitialized = false;
        $attrs.$observe('ng-model', function (newValue) {
          if (newValue) {
            console.log('my model', ngModelCtrl);
          }
        });
      }
    }
  });
index.html
<!DOCTYPE html>
<html ng-app="treehouseCourse">
<head>
  <title>Angular.js</title>
  <script src="js/angular.js"></script>
  <script src="app.js"></script>
</head>
<body>

  <sometimes-two-way ng-model="course.description"></sometimes-two-way>

</body>
</html>

1 Answer

Paul Razgaitis
Paul Razgaitis
11,362 Points

Derek,

I don't think you need to include the isInitialized variable to check if ngModelCtrl is defined, you can just include it in the if statement like this: if(ngModelCtrl) { do something} else { do something else}.

This is the code that worked for me:

angular.module('treehouseCourse', [])
  .directive('sometimesTwoWay', function() {
    return {
      // YOUR CODE HERE
      require: '?ngModel',
      link: function($scope, $element, $attrs, ngModelCtrl) {
        if(ngModelCtrl) {
          console.log('my model', ngModelCtrl);
        } else {
          return;
        }
      }
    }
  });