ExtReact Docs Help


The documentation for the ExtReact product diverges somewhat from the documentation of other Sencha products. The sections below describe documentation for all products except where indicated as unique to ExtReact.

Terms, Icons, and Labels

Many classes have shortcut names used when creating (instantiating) a class with a configuration object. The shortcut name is referred to as an alias (or xtype if the class extends Ext.Component). The alias/xtype is listed next to the class name of applicable classes for quick reference.

ExtReact component classes list the configurable name prominently at the top of the API class doc followed by the fully-qualified class name.

Access Levels

Framework classes or their members may be specified as private or protected. Else, the class / member is public. Public, protected, and private are access descriptors used to convey how and when the class or class member should be used.

Member Types

Member Syntax

Below is an example class member that we can disect to show the syntax of a class member (the lookupComponent method as viewed from the Ext.button.Button class in this case).

lookupComponent ( item ) : Ext.Component

Called when a raw config object is added to this container either during initialization of the items config, or when new items are added), or {@link #insert inserted.

This method converts the passed object into an instanced child component.

This may be overridden in subclasses when special processing needs to be applied to child creation.


item :  Object

The config object being added.


The component to be added.

Let's look at each part of the member row:

Member Flags

The API documentation uses a number of flags to further commnicate the class member's function and intent. The label may be represented by a text label, an abbreviation, or an icon.

Class Icons

- Indicates a framework class

- A singleton framework class. *See the singleton flag for more information

- A component-type framework class (any class within the Ext JS framework that extends Ext.Component)

- Indicates that the class, member, or guide is new in the currently viewed version

Member Icons

- Indicates a class member of type config

Or in the case of an ExtReact component class this indicates a member of type prop

- Indicates a class member of type property

- Indicates a class member of type method

- Indicates a class member of type event

- Indicates a class member of type theme variable

- Indicates a class member of type theme mixin

- Indicates that the class, member, or guide is new in the currently viewed version

Class Member Quick-Nav Menu

Just below the class name on an API doc page is a row of buttons corresponding to the types of members owned by the current class. Each button shows a count of members by type (this count is updated as filters are applied). Clicking the button will navigate you to that member section. Hovering over the member-type button will reveal a popup menu of all members of that type for quick navigation.

Getter and Setter Methods

Getting and setter methods that correlate to a class config option will show up in the methods section as well as in the configs section of both the API doc and the member-type menus just beneath the config they work with. The getter and setter method documentation will be found in the config row for easy reference.

ExtReact component classes do not hoist the getter / setter methods into the prop. All methods will be described in the Methods section

History Bar

Your page history is kept in localstorage and displayed (using the available real estate) just below the top title bar. By default, the only search results shown are the pages matching the product / version you're currently viewing. You can expand what is displayed by clicking on the button on the right-hand side of the history bar and choosing the "All" radio option. This will show all recent pages in the history bar for all products / versions.

Within the history config menu you will also see a listing of your recent page visits. The results are filtered by the "Current Product / Version" and "All" radio options. Clicking on the button will clear the history bar as well as the history kept in local storage.

If "All" is selected in the history config menu the checkbox option for "Show product details in the history bar" will be enabled. When checked, the product/version for each historic page will show alongside the page name in the history bar. Hovering the cursor over the page names in the history bar will also show the product/version as a tooltip.

Search and Filters

Both API docs and guides can be searched for using the search field at the top of the page.

On API doc pages there is also a filter input field that filters the member rows using the filter string. In addition to filtering by string you can filter the class members by access level, inheritance, and read only. This is done using the checkboxes at the top of the page.

The checkbox at the bottom of the API class navigation tree filters the class list to include or exclude private classes.

Clicking on an empty search field will show your last 10 searches for quick navigation.

API Doc Class Metadata

Each API doc page (with the exception of Javascript primitives pages) has a menu view of metadata relating to that class. This metadata view will have one or more of the following:

Expanding and Collapsing Examples and Class Members

Runnable examples (Fiddles) are expanded on a page by default. You can collapse and expand example code blocks individually using the arrow on the top-left of the code block. You can also toggle the collapse state of all examples using the toggle button on the top-right of the page. The toggle-all state will be remembered between page loads.

Class members are collapsed on a page by default. You can expand and collapse members using the arrow icon on the left of the member row or globally using the expand / collapse all toggle button top-right.

Desktop -vs- Mobile View

Viewing the docs on narrower screens or browsers will result in a view optimized for a smaller form factor. The primary differences between the desktop and "mobile" view are:

Viewing the Class Source

The class source can be viewed by clicking on the class name at the top of an API doc page. The source for class members can be viewed by clicking on the "view source" link on the right-hand side of the member row.

ExtReact 7.1.0


Ext.Loader singleton

NPM Package





This class provides dynamic loading support for JavaScript classes. Application code does not typically need to call Ext.Loader except perhaps to configure path mappings when not using Sencha Cmd.

 Ext.Loader.setPath('MyApp', 'app');

When using Sencha Cmd, this is handled by the "bootstrap" provided by the application build script and such configuration is not necessary.

Typical Usage

The Ext.Loader is most often used behind the scenes to satisfy class references in class declarations. Like so:

 Ext.define('MyApp.view.Main', {
     extend: 'Ext.panel.Panel',

     mixins: [

     requires: [

     uses: [

In all of these cases, Ext.Loader is used internally to resolve these class names and ensure that the necessary class files are loaded.

During development, these files are loaded individually for optimal debugging. For a production use, Sencha Cmd will replace all of these strings with the actual resolved class references because it ensures that the classes are all contained in the build in the correct order. In development, these files will not be loaded until the MyApp.view.Main class indicates they are needed as shown above.

Loading Classes

You can also use Ext.Loader directly to load classes or files. The simplest form of use is Ext#require.

For example:

 Ext.require('MyApp.view.Main', function () {
     // On callback, the MyApp.view.Main class is now loaded

     var view = new MyApp.view.Main();

You can alternatively require classes by alias or wildcard.


Ext.require(['widget.window', 'layout.border', 'Ext.data.Connection']);

Ext.require(['widget.*', 'layout.*', 'Ext.data.*']);

The callback function is optional.

Note Using Ext.require at global scope will cause Ext#onReady and Ext.app.Application#launch methods to be deferred until the required classes are loaded. It is these cases where the callback function is most often unnecessary.

Using Excludes

Alternatively, you can exclude what you don't need:

// Include everything except Ext.tree.*

// Include all widgets except widget.checkbox* (this will exclude
// widget.checkbox, widget.checkboxfield, widget.checkboxgroup, etc.)

Dynamic Instantiation

Another feature enabled by Ext.Loader is instantiation using class names or aliases.

For example:

 var win = Ext.create({
     xtype: 'window',

     // or
     // xclass: 'Ext.window.Window'

     title: 'Hello'

This form of creation can be useful if the type to create (window in the above) is not known statically. Internally, create may need to synchronously load the desired class and its requirements. Doing this will generate a warning in the console:

 [Ext.Loader] Synchronously loading 'Ext.window.Window'...

If you see these in your debug console, you should add the indicated class(es) to the appropriate requires array (as above) or make an Ext#require call.

Note Using create has some performance overhead and is best reserved for cases where the target class is not known until run-time.

No members found using the current filters


Optional Configs

disableCaching : Boolean

Appends current timestamp to script files to prevent caching.

Defaults to:


disableCachingParam : String

The get parameter name for the cache buster's timestamp.

Defaults to:


enabled : Boolean

Whether or not to enable the dynamic dependency loading feature.

Defaults to:


paths : Object

The mapping from namespaces to file paths

    'Ext': '.', // This is set by default, Ext.layout.container.Container will be
                // loaded from ./layout/Container.js

    'My': './src/my_own_folder' // My.layout.Container will be loaded from
                                // ./src/my_own_folder/layout/Container.js

Note that all relative paths are relative to the current HTML document. If not being specified, for example, Other.awesome.Class will simply be loaded from "./Other/awesome/Class.js".

Defaults to:


preserveScripts : Boolean

false to remove asynchronously loaded scripts, true to retain script element for browser debugger compatibility and improved load performance.

Defaults to:


scriptChainDelay : Boolean

millisecond delay between asynchronous script injection (prevents stack overflow on some user agents) 'false' disables delay but potentially increases stack load.

Defaults to:


scriptCharset : String

Optional charset to specify encoding of dynamic script content.

Defaults to:



Instance Properties

private pri

Defaults to:


private pri


Defaults to:


private pri

Defaults to:


history : Array

An array of class names to keep track of the dependency loading order. This is not guaranteed to be the same everytime due to the asynchronous nature of the Loader.

Defaults to:


private pri

Defaults to:


private pri

Flag indicating whether there are still files being loaded

Defaults to:


private pri

Contains classes referenced in uses properties.

Defaults to:


private pri

Maintain the list of listeners to execute when all required scripts are fully loaded

Defaults to:


private pri

Map of fully qualified class names to an array of dependent classes.

Defaults to:


private pri

The number of scripts loading via loadScript.

Defaults to:


private pri

Defaults to:



Instance Methods

addBaseUrlClassPathMappings ( pathConfig )

fixes up loader path configs by prepending Ext.Boot#baseUrl to the beginning of the path, then delegates to Ext.Loader#addClassPathMappings


pathConfig :  Object

addClassPathMappings ( paths ) : Ext.Loader

Sets a batch of path entries


paths :  Object

a set of className: path mappings




addUsedClasses ( classes )
private pri

Ensure that any classes referenced in the uses property are loaded.


classes :  Object

getConfig ( name ) : Object

Get the config value corresponding to the specified name. If no name is given, will return the config object


name :  String

The config property name



getPath ( className ) : String

Translates a className to a file path by adding the the proper prefix and converting the .'s to /'s. For example:

Ext.Loader.setPath('My', '/path/to/My');

// alerts '/path/to/My/awesome/Class.js'

Note that the deeper namespace levels, if explicitly set, are always resolved first. For example:

    'My': '/path/to/lib',
    'My.awesome': '/other/path/for/awesome/stuff',
    'My.awesome.more': '/more/awesome/path'

// alerts '/other/path/for/awesome/stuff/Class.js'

// alerts '/more/awesome/path/Class.js'

// alerts '/path/to/lib/cool/Class.js'

// alerts 'Unknown/strange/Stuff.js'


className :  String




historyPush ( className )
private pri


className :  String

loadScript ( options )

Loads the specified script URL and calls the supplied callbacks. If this method is called before Ext#isReady, the script's load will delay the transition to ready. This can be used to load arbitrary scripts that may contain further Ext.require calls.


options :  Object/String/String[]

The options object or simply the URL(s) to load.

url :  String

The URL from which to load the script.

onLoad :  Function (optional)

The callback to call on successful load.

onError :  Function (optional)

The callback to call on failure to load.

scope :  Object (optional)

The scope (this) for the supplied callbacks.

loadScripts ( params )
private pri

This is an internal method that delegate content loading to the bootstrap layer.


params :  Object

loadScriptsSync ( urls )
private pri

This method is provide for use by the bootstrap layer.


urls :  String[]

loadScriptsSyncBasePrefix ( urls )
private pri

This method is provide for use by the bootstrap layer.


urls :  String[]

onReady ( fn, scope, [withDomReady], [options] )

Add a new listener to be executed when all required scripts are fully loaded


fn :  Function

The function callback to be executed

scope :  Object

The execution scope (this) of the callback function.

withDomReady :  Boolean (optional)

Pass false to not also wait for document dom ready.

Defaults to: true

options :  Object (optional)

Additional callback options.

delay :  Number (optional)

A number of milliseconds to delay.

Defaults to:


priority :  Number (optional)

Relative priority of this callback. Negative numbers are reserved.

Defaults to:


setConfig ( config ) : Ext.Loader

Set the configuration for the loader. This should be called right after ext-(debug).js is included in the page, and before Ext.onReady. i.e:

<script type="text/javascript" src="ext-core-debug.js"></script>
<script type="text/javascript">
      enabled: true,
      paths: {
          'My': 'my_own_path'
<script type="text/javascript">

    Ext.onReady(function() {
      // application code here

Refer to config options of Ext.Loader for the list of possible properties


config :  Object

The config object to override the default values




setPath ( name, [path] ) : Ext.Loader

Sets the path of a namespace. For Example:

Ext.Loader.setPath('Ext', '.');


name :  String/Object

path :  String (optional)




ExtReact 7.1.0