Yes Yes - 3 months ago 5x
AngularJS Question

scope & trigger in angular1

Could you point me to the right direction what I should look up in order to understand the following code about

trigger: "=trigger"

app.module.directive('messageModal', function ($compile) {
return {
scope: {
trigger: "=trigger",

controller: ['$scope', '$element', '$attrs', '$timeout', function ($scope, $element, $attrs, $timeout) {
$scope.trigger = function(title, message, modal_class, color, auto_hide){

What I understand is that by having
scope: {},
the directive
has created a brand new scope object. BUT what does
trigger: "=trigger"
do? What about the

Please I need some directions on what I should learn in order to understand what the directive does. Thanks!


Properties within scope option are mappings between each property and an attribute in the directive markup when you're using it somewhere.

Scope's property value defines how scope properties are bound:

  • = means two-way binding
  • @ means literal binding.
  • & means function binding.

A scope property can be provided in two ways (with any of above described bindings):

  • { some: "=" } which means that scope property and its HTML attribute counterpart will share the same identifier.
  • { some: "=whatever" } allows you to define how will be identified the attribute bound to the whole scope property.

Once an isolated scope has already bound properties and attributes, you'll access them injecting $scope and accessing the property: $scope.whatever.