Where should I define global functions in ExtJS 4 MVC?

Question

I need to define some functions which i can call everywhere in my app. What is the best approach to achieve this?

Solution 1

Personally, to keep it as EXT-MVC as possible, I have a Utilities class full of static methods. This can be required like any other class to maintain proper dependency relations. This also ensures that the methods are run in an EXT environment, so all of EXT is available.

Ext.define('MyApp.Utilities', {
    statics: {
        foo: function (a, b) {
            return a + b;
        }
    }
});

Ext.define('MyApp.MyView', {
    extends: 'Ext.panel.Panel',
    requires: ['MyApp.Utilities'],

    initComponent: function () {
        MyApp.Utilities.foo(1, 2);
    }
});

Solution 2

An alternative way other than @David Kanarek's statics approach is to define a singleton. Codes:

Ext.define('MyApp.Utilities2', {
    singleton: true,
    global_var2: 'Hello World',
    foo2: function (a, b) {
        return a + b;
    },
});

I've created a fiddle here: https://fiddle.sencha.com/#fiddle/qu1

The difference between the statics and singleton approach is that

• MyApp.Utilities2 (singleton approach) is an object,
• MyApp.Utilities (statics approach) is a class.

So It's up to you whether to reference the class itself or to reference one instance of that class for convenience.

Comments

[s.webbandit]

Can you provide some little example of your idea?

[JohnnyHK]

Shouldn't the Utilities.foo call be MyApp.Utilities.foo?

[Kirill]

That's what I get for changing the namespace at the last minute. Fixed, thanks.

[darren]

Great answer. As a side note in Sencha Architect you can add the utility class JS file as a Resource to the project.

[Raza Ahmed]

What if not want to return anything??

[A.W.]

Cool solution! I put it in /util/ folder

[Handsome Nerd]

@RazaAhmed What do you mean? The function in the example is not a void method.