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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.

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

- 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.

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.

Ext JS 7.4.0 - Modern Toolkit

Guide applies to: modern

Utilizing Sencha Cmd Build Options and Dynamic Package Loading with ExtGen

With Open Tooling, @sencha/[email protected], and later you can unlock many build features of Sencha Cmd by passing environment options through your npm scripts. These options are then sent to Sencha Cmd via Sencha's custom webpack plugin.

Open Tooling uses Sencha Cmd under the hood to drive Ext JS build process. You may want to read this Sencha CMD Reference before getting started if you haven't used Sencha Cmd before.

npm Scripts

To take advantage of this new ext-gen feature, most of our work will happen in the package.json file that npm uses as a manifest. This file is created when you create an Ext JS open tooling application using ext-gen.

Notice the scripts object in the package.json file. These scripts are written as usual JSON key-value pairs where the key is the name of the script and the value contains the script you want to execute.

Here is an example:

"scripts": {    "start": "node index.js",    ...}

Cmd Opts: Dynamic Packages

Sencha CMD offers a smart way for your production app to load packages dynamically by using the package-loader package. This package is available on Sencha's private npm registry, or through Sencha's package repository managed by Sencha Cmd.

1. Add the package-loader

Configure app.json to use the package-loader package by adding it to the requires:[] array like this:


Sencha Cmd will automically downnload and install the package-loader package into the packages directory of your application.

2. Add Your Packages

Configure the packages you need to load dynamically by adding a uses:[...] array to app.json and adding a new entry for each package you want dynamically loaded.


3. Update Your npm Build Scripts

Enable the dynamic package loader from your scripts by passing an environment variable through the webpack plugin: --env.cmdopts=--uses. You may recognize this is the same flag used by Sencha Cmd CLI. Sencha's custom webpack plugin exposes the variable cmdopts to your npm scripts. Within the webpack plugin, this variable is parsed into an array of build options for Sencha Cmd.

Example production build script:

"build": "npm run clean && cross-env webpack --env.profile=desktop --env.treeshake=yes --env.verbose=no  --env.cmdopts=--environment=production --env.cmdopts=--uses"

4. Try it!

Run your build scripts (defaults are provided with 7.4 generated applications), ensuring the cmpopts are set in environment variables and watch your packages load dynamically!

Explore the Dynamic Package Loader docs for more information.

Cmd Opts: Build Types

There are 3 different build types for an Ext JS application.

  1. development: uses non-bundled assets, local manifest files, for debugging purposes.
  2. testing: Simulates the production build assets.
  3. production: Build a production, deployment-ready set of arifacts for your application.

NOTE: --env.cmdopts supersedes --env.environment

Building for Development

When developing an app with ext-gen you need to a local webserver that updates automatically with as you develop your source files. The npm start default script uses the Sencha Cmd app watch command to build a development copy of your app and host it on a local webserver. app watch "watches" for file changes and triggers a reload.

// Development build
"dev": "webpack-dev-server --env.profile=desktop --env.browser=yes --env.verbose=no --env.cmdopts=--environment=development --env.cmdopts=--uses",

Building for Testing

Before building for production it is very important to test your built app. Testing builds provide you a way to build and compress your code without minifying and obfuscating. This gives you an easy way of debugging a built application in a “human-debuggable“ mode. Run the testing build script and ensure --env.cmdopts are set. This will instruct webpack pass the options to Sencha CMD.

// Testing build
"build:testing": "npm run clean && cross-env webpack --env.profile=desktop --env.treeshake=yes --env.verbose=yes --env.cmdopts=--build=desktop --env.cmdopts=--environment=testing --env.cmdopts=--uses --env.cmdopts=--destination=testing"

Building for Production

// Production Build
"build": "npm run clean && cross-env webpack --env.profile=desktop --env.treeshake=yes --env.verbose=yes --env.cmdopts=--environment=production --env.cmdopts=--uses",

Available Cmd Opts

The following cmdopts are allowed in Open Tooling ext-gen applications as options for the Sencha Cmd build sequence


  • --archive, -a - The directory path where all previous builds were stored.
  • --build, -build - Selects the name of the build specified in the 'builds' app.json set to use for the build
  • --clean, -c - Remove previous build output prior to executing build
  • --destination, -des - The directory to which the build output is written
  • --development, -dev - Sets the build environment to: development
  • --environment, -e - The build environment, either 'development', 'testing' or 'production'
  • --fashion-debug, -fashion-d - Enables / disables node dev tools when running fashion builds.
  • --fashion-symbols, -fashion-s - Enables / disables stack traces in scss code.
  • --locale, -l - Selects the app.locale setting to use for the build
  • --packages, -pac - Only build one or more of the packages specified in the "uses" property on app.json
  • --pkg-environment, -pkg - The build environment for used packages, either 'development', 'testing' or 'production'
  • --pkgdevelopment, -pkgd - Sets the build environment for used packages to: development
  • --pkgproduction, -pkgp - Sets the build environment for used packages to: production
  • --pkgtesting, -pkgt - Sets the build environment for used packages to: testing
  • --production, -pr - Sets the build environment to: production
  • --run, -r - Enables automatically running builds with the native packager
  • --testing, -te - Sets the build environment to: testing
  • --theme, -th - Selects the app.theme setting to use for the build
  • --uses, -u - Build the packages dynamically used by this application (see "uses" on app.json)


  • --env.cmdopts=--option || -opt

More Information

Sencha Cmd packages

Dynamic Package Loader - manifest object

Ext JS 7.4.0 - Modern Toolkit