BackboneJS-View undelegateEvents

Description

It is used to remove delegated events of the view from the DOM.

Syntax

delegateEvents()

Example

<!DOCTYPE html>
   <head>
      <title>View Example</title>
      <script src = "https://code.jquery.com/jquery-2.1.3.min.js" 
         type = "text/javascript"></script>
      
      <script src = "https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.2/underscore-min.js" 
         type = "text/javascript"></script>
      
      <script src = "https://cdnjs.cloudflare.com/ajax/libs/backbone.js/1.1.2/backbone-min.js"  
         type = "text/javascript"></script>
   </head>
   
   <body>
      <div id = "mydiv"></div>
      <script type = "text/javascript">
         //'ViewDemo' is a name of the view class
         var ViewDemo = Backbone.View.extend({

            //When click event occurs it activates the defined function 'undelegateFunc'
            events: {'click button': 'undelegateFunc'}, undelegateFunc: function () {
               document.write("do something...");
               $(this.el).undelegate('button', 'click');
            },

            //'render' provides the logic required to construct the view
            render: function () {

               //'$el' is cached object that push the content defined within it and
               //display the value when user clicks the button
               this.$el.html('<button>Click to undelegate</button>');
            },

            //This function is called when the view is instantiated
            initialize:function(){this.render();}
         });

         //'myview' is an instance of the 'ViewDemo' class
         var myview = new ViewDemo({el: '#mydiv'});
      </script>
      
   </body>
</html>

Output

Let's carry out the following steps to see how above code works:

Save above code in undelegateEvents.htm file
Open this HTML file in a browser.

backbonejs_view.htm

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