Question

I am creating a form builder application using backbonejs and would like to know how load view dynamically
I have a dropdown where i can choose what type of element should be added eg i choose input field. i have some default values that go with every element they are in formstemplate and based on what field is chosen i want to load different html templates.

define([
  'jquery',
  'underscore',
  'backbone',
  'modal',
// Pull in the Collection module from above
  'collections/builder',
  'text!templates/forms/builder.html',
  'text!templates/forms/formsTemplate.html',
  'text!templates/forms/textBox.html',
  'models/builder'

], function ($, _, Backbone, popupModal, attributesCollection, builderTemplate, formsTemplate, inputTemplate, attributesModel) {
    var attributesBuilderView = Backbone.View.extend({
        el: $("#page"),
        initialize: function () {

        },
        render: function () {
            this.loadTemplate();
        },
        loadTemplate: function () {
            var that = this;
            this.el.html(builderTemplate);
        },
        // Listen to events on the current el
        events: {
            "change #attributeType": "loadAttributeTemplate"
        },
        loadAttributeTemplate: function () {
            if ( ($("#attributeType").val()) != '0') {
                $("#attributesArea").append(_.template(formsTemplate, { elementType:              $("#attributeType :selected").text(), _: _ }));
                var template = $("#attributeType").val() + 'Template';
                $(".formElement").html(_.template(template));
            }
        }
    });
    return new attributesBuilderView;
});

here when i run this code i get inputTemplate text in the html rather than template if i put $(“.formElement”).html(_.template(inputTemplate)); it works fine. I just need to know how to load these dynamically

Thanks in advance

Answer 1

You can place the require call anywhere if you only want to do conditional loading:

edited (added the function params to the require statement)

loadAttributeTemplate: function () {
    if ( ($("#attributeType").val()) != '0') {
        require(['text!templates/forms/builder.html',
            'text!templates/forms/formsTemplate.html',
            'text!templates/forms/textBox.html'], 
            _.bind(function(builder, formsTemplate, textBox) {
                $("#attributesArea").append(_.template(formsTemplate, { elementType:               $("#attributeType :selected").text(), _: _ }));
                var template = $("#attributeType").val() + 'Template';
                $(".formElement").html(_.template(template));
            },this);
        );
    }
}

Note, I also did a _.bind(…,this) to maintain the execution scope. I know that’s not necessarily needed here, but it does come in handy.

I do this in a few places in my application; especially when I want to load modules only if and when I need them.