BackboneJS - Collection Pop



Description

It is similar to the remove() method which takes the array of models and remove the models from the collection.

Syntax

collection.pop(models, options)

Parameters

  • models − It contains the names of the collection instances, which are needed to be popped out from the collection.

  • options − It includes the model type which will be removed from the collection.

Example

<!DOCTYPE html>
<html>
   <head>
      <title>Collection 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>
      <script type = "text/javascript">
         
         //The 'Player' is a model name and includes the default values
         var Player = Backbone.Model.extend ({
            defaults: {
               c_id:"",
               country: ""
            }
         });
         
         //The 'PlayersCollection' is a collection instance and model 'Player' is specified by using model property
         var PlayersCollection = Backbone.Collection.extend ({
            model: Player
         });
         
         //The 'country1', 'country2' and 'country3' are instances of the model 'Player'
         var country1 = new Player({c_id:1, country: "australia" });
         var country2 = new Player({c_id:2, country: "england"});
         var country3 = new Player({c_id:3, country: "india"});
         var mycollection = new PlayersCollection();

         //Here, the push() method adds the above models to the collection
         mycollection.push(country1);
         mycollection.push(country2);
         mycollection.push(country3);
         document.write('Number of pushed countries : ' + mycollection.length);
         document.write("<br>");

         //The pop() method removes the models from the collection
         mycollection.pop(country1);
         mycollection.pop(country2);
         mycollection.pop(country3);
         document.write('Number of popped countries : ' + mycollection.length);
      </script>
   </body>
</html>

Output

Let us carry out the following steps to see how the above code works −

  • Save the above code in the pop.htm file.

  • Open this HTML file in a browser.

backbonejs_collection.htm
Advertisements