Question

I’m building a web application with various visualization components, made up of Backbone.js Models and Views:

The “PopulationVisualization component” might for example have:

• a main model – storing the state of the component
• several Backbone views (timesliderView, legendView etc.) – listening to changes on the model

All of these components depend on external dataManagers and dataSource objects but otherwise they are supposed to be decoupled.

On a given page, I’d like to instantiate an instance of the PopulationVisualization component. I’d also like to listen for changes in the main model of that component so that I could serialize its state in the URL.

1) What would this look like if I tried adopting the AMD module pattern?
2) Would I make one module of the PopulationVisualization component or several?
3) Would I expose module-level methods as an API or would I provide direct manipulation of the inner Models and Views?

Thanks.

Answer 1

To answer you questions, here’s my advice, answering all three:

Modules should be as small as possible, so I would create a new module for each view, one for the module, and one for the serialization logic. Then I would create one module that ties all this together so that outside code doesn’t have to deal with models, views, or serialization.

---

Here is my first stab at something like this:

// components/populationVisualization/Model.js
define(function (require, exports, module) {
  return Backbone.Model.extend({ /* ... */});
});

// components/populationVisualization/views/Timeslider.js
define(function (require, exports, module) {
  return Backbone.View.extend({ /* ... */});
});

// components/populationVisualization/views/Legend.js
define(function (require, exports, module) {
  return Backbone.View.extend({ /* ... */});
});

// components/populationVisualization/serializer.js
define(function (require, exports, module) {
  exports.setupSerialization = function (model) {
    // ...
  };
});

// components/populationVisualization.js
define(function (require, exports, module) {
  var Model = require("./populationVisualization/Model");
  var TimesliderView = require("./populationVisualization/views/Timeslider");
  var LegendView = require("./populationVisualization/views/Legend");
  var serializer = require("./populationVisualization/serializer");

  exports.createAndRender = function (modelParams, $el) {
    var model = new Model(modelParams);
    serializer.setupSerialization(model);

    var timesliderView = new TimesliderView({ model: model });
    var legendView = new LegendView({ model: model });

    $el.append(timesliderView.el);
    $el.append(legendView.el);
  };
});

Elsewhere in the app you would only require("components/populationVisualization") and call that module’s createAndRender method with the appropriate parameters.