Javascript Cheatsheet

There are many ways to solve a problem in JavaScript, and in Odoo. However, the Odoo framework was designed to be extensible (this is a pretty big constraint), and some common problems have a nice standard solution. The standard solution has probably the advantage of being easy to understand for an odoo developers, and will probably keep working when Odoo is modified.

This document tries to explain the way one could solve some of these issues. Note that this is not a reference. This is just a random collection of recipes, or explanations on how to proceed in some cases.

First of all, remember that the first rule of customizing odoo with JS is: try to do it in python. This may seem strange, but the python framework is quite extensible, and many behaviours can be done simply with a touch of xml or python. This has usually a lower cost of maintenance than working with JS:

  • the JS framework tends to change more, so JS code needs to be more frequently updated
  • it is often more difficult to implement a customized behaviour if it needs to communicate with the server and properly integrate with the javascript framework. There are many small details taken care by the framework that customized code needs to replicate. For example, responsiveness, or updating the url, or displaying data without flickering.

Creating a new field widget

This is probably a really common usecase: we want to display some information in a form view in a really specific (maybe business dependent) way. For example, assume that we want to change the text color depending on some business condition.

This can be done in three steps: creating a new widget, registering it in the field registry, then adding the widget to the field in the form view

  • creating a new widget:

    This can be done by extending a widget:

    var FieldChar = require('web.basic_fields').FieldChar;
    var CustomFieldChar = FieldChar.extend({
        _renderReadonly: function () {
            // implement some custom logic here
  • registering it in the field registry:

    The web client needs to know the mapping between a widget name and its actual class. This is done by a registry:

    var fieldRegistry = require('web.field_registry');
    fieldRegistry.add('my-custom-field', CustomFieldChar);
  • adding the widget in the form view
    <field name="somefield" widget="my-custom-field"/>

    Note that only the form, list and kanban views use this field widgets registry. These views are tightly integrated, because the list and kanban views can appear inside a form view).

Modifying an existing field widget

Another use case is that we want to modify an existing field widget. For example, the voip addon in odoo need to modify the FieldPhone widget to add the possibility to easily call the given number on voip. This is done by including the FieldPhone widget, so there is no need to change any existing form view.

Field Widgets (instances of (subclass of) AbstractField) are like every other widgets, so they can be monkey patched. This looks like this:

var basic_fields = require('web.basic_fields');
var Phone = basic_fields.FieldPhone;

    events: _.extend({},, {
        'click': '_onClick',

    _onClick: function (e) {
        if (this.mode === 'readonly') {
            var phoneNumber = this.value;
            // call the number on voip...

Note that there is no need to add the widget to the registry, since it is already registered.

Modifying a main widget from the interface

Another common usecase is the need to customize some elements from the user interface. For example, adding a message in the home menu. The usual process in this case is again to include the widget. This is the only way to do it, since there are no registries for those widgets.

This is usually done with code looking like this:

var HomeMenu = require('web_enterprise.HomeMenu');

    render: function () {
        // do something else here...

Creating a new view (from scratch)

Creating a new view is a more advanced topic. This cheatsheet will only highlight the steps that will probably need to be done (in no particular order):

  • adding a new view type to the field type of ir.ui.view:

    class View(models.Model):
        _inherit = 'ir.ui.view'
        type = fields.Selection(selection_add=[('map', "Map")])
  • adding the new view type to the field view_mode of ir.actions.act_window.view:

    class ActWindowView(models.Model):
        _inherit = 'ir.actions.act_window.view'
        view_mode = fields.Selection(selection_add=[('map', "Map")])
  • creating the four main pieces which makes a view (in JavaScript):

    we need a view (a subclass of AbstractView, this is the factory), a renderer (from AbstractRenderer), a controller (from AbstractController) and a model (from AbstractModel). I suggest starting by simply extending the superclasses:

    var AbstractController = require('web.AbstractController');
    var AbstractModel = require('web.AbstractModel');
    var AbstractRenderer = require('web.AbstractRenderer');
    var AbstractView = require('web.AbstractView');
    var MapController = AbstractController.extend({});
    var MapRenderer = AbstractRenderer.extend({});
    var MapModel = AbstractModel.extend({});
    var MapView = AbstractView.extend({
        config: {
            Model: MapModel,
            Controller: MapController,
            Renderer: MapRenderer,
  • adding the view to the registry:

    As usual, the mapping between a view type and the actual class needs to be updated:

    var viewRegistry = require('web.view_registry');
    viewRegistry.add('map', MapView);
  • implementing the four main classes:
    The View class needs to parse the arch field and setup the other three classes. The Renderer is in charge of representing the data in the user interface, the Model is supposed to talk to the server, to load data and process it. And the Controller is there to coordinate, to talk to the web client, …
  • creating some views in the database:
    <record id="customer_map_view" model="ir.ui.view">
        <field name="name"></field>
        <field name="model">res.partner</field>
        <field name="arch" type="xml">
            <map latitude="partner_latitude" longitude="partner_longitude">
                <field name="name"/>

Customizing an existing view

Assume we need to create a custom version of a generic view. For example, a kanban view with some extra ribbon-like widget on top (to display some specific custom information). In that case, this can be done with 3 steps: extend the kanban view (which also probably mean extending controllers/renderers and/or models), then registering the view in the view registry, and finally, using the view in the kanban arch (a specific example is the helpdesk dashboard).

  • extending a view:

    Here is what it could look like:

    var HelpdeskDashboardRenderer = KanbanRenderer.extend({
    var HelpdeskDashboardModel = KanbanModel.extend({
    var HelpdeskDashboardController = KanbanController.extend({
    var HelpdeskDashboardView = KanbanView.extend({
        config: _.extend({}, KanbanView.prototype.config, {
            Model: HelpdeskDashboardModel,
            Renderer: HelpdeskDashboardRenderer,
            Controller: HelpdeskDashboardController,
  • adding it to the view registry:

    as usual, we need to inform the web client of the mapping between the name of the views and the actual class.

    var viewRegistry = require('web.view_registry');
    viewRegistry.add('helpdesk_dashboard', HelpdeskDashboardView);
  • using it in an actual view:

    we now need to inform the web client that a specific ir.ui.view needs to use our new class. Note that this is a web client specific concern. From the point of view of the server, we still have a kanban view. The proper way to do this is by using a special attribute js_class (which will be renamed someday into widget, because this is really not a good name) on the root node of the arch:

    <record id="helpdesk_team_view_kanban" model="ir.ui.view" >
        <field name="arch" type="xml">
            <kanban js_class="helpdesk_dashboard">