Client runtime dependencies

On the client side in RAIN we use requirejs (http://requirejs.org) for loading scripts in a non blocking way. This gives RAIN client side great speed and asynchronicity. Each javascript code is grouped and exposed as a requirejs module. Below you can find a list of objects that are provided to you all the time:

• Context
• Messaging
• jquery

You will never have to require this modules as they are already accessible from you client side controller.

Client side controller

Client side controller is a special requirejs module that is automatically bound to a view. You can find out how to do this by reading RAIN component descriptor. Currently, client side controllers have two special methods that are automatically invoked:

define(function() {

    function Controller() {}

    Controller.prototype.init = function () {
        // Here you don't have access to the DOM tree so please don't do DOM transformations.
        // You have full access to the context object:

        alert(this.context);
    };

    Controller.prototype.start = function () {
        // Here you should place all DOM transformations.
    };

    return Controller;
});

Including other modules

To include other requirejs modules to you client side controller you can use the following:

define(function() {

    function Controller() {}

    Controller.prototype.init = function () {
        require(["<path to dep1>", "<path to dep2>"], function(dep1, dep2)) {
            // do something when everything is loaded.
        };
    };

    return Controller;
});

Each component is automatically included in the bootstrap sequence which means you have a shortcut to include javascript from it:

define(["my-module/module_helper1"], function (moduleHelper1) {
    // Do something with moduleHelper1
});

my-module is your module identifier as described in component descriptor (see RAIN component descriptor). This is really easy and gives you the advantage of not knowing the absolute path of the module javascript files. This is automatically set up for you by RAIN.

Why do we even use requirejs?

Requirejs automatically namespace javascript code. This mean that we do not pollute window object and moreover we can easily aggregate modules without a single javascript clash. Moreover your code is easily to maintain using this approach.