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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.



Sencha Cmd Packages

Sencha Cmd includes the Sencha Package Manager. There are two basic problems that packages are designed to solve: consumption and distribution. This guide focused on these topics. See also Creating Sencha Cmd Packages for information about creating and sharing a package.

The "packages" Folder

All workspaces generated by Sencha Cmd have a "packages" folder at the root. The location of this folder can be configured, but regardless of its location, the role of the "packages" folder is to serve as the storage of all packages used by the applications (or other packages) in the workspace.

packages/       # Container folder for shared Cmd packages
    local/      # Folder for packages generated in this workspace
    remote/     # Folder for packages downloaded into the workspace

Packages will be added to the "packages/remote" folder when they are required by an application and are downloaded to satisfy the requirement. When a package is generated (using sencha generate package), it is generated into "packages/local".

Requiring Packages in Applications

Regardless of the origin of a package (whether it was created locally or downloaded from a remote repository - see below), consuming the package is the same: you add an entry to the requires array in "app.json". For demonstration purposes, we have added a simple package that you can experiment with:

    "name": "MyApp",
    "requires": [

Given the above requirements, sencha app build and sencha app refresh will both now perform the steps needed to integrate the package in to your application. Typically, after changing package requirements, you will need to run sencha app refresh so that the metadata required to support "dev mode" is up to date.

Whichever command you run, Sencha Cmd will download and expand the package to your "packages/remote" folder. After this you will find a "packages/remote/cool-stuff" folder in your workspace.

Local Packages

One use of packages is simply to hold code or themes that are available for multiple applications in the workspace. These packages need never be distributed (beyond source control) to provide value to your development.

To add a package to your workspace, you just generate the package:

sencha generate package common

This generates a new package to the "packages/local/common" folder. This package is also marked as local: true in its "package.json". This flag prevents Sencha Cmd from ever overwriting the package with a version from a remote repository (see below). This would become important if the packages folders were combined (as they were in previous releases) by editing "workspace.json".

Then add "common" as a requirement to your application's "app.json" as described above:

    "name": "MyApp",
    "requires": [

For more details, especially regarding how to distribute packages to others, see Creating Sencha Cmd Packages.

Remote Packages

While local packages can be very valuable in large applications, one of the most useful aspects of packages is the ability to distribute packages for others to consume.

Packages are shared and distributed using package repositories. Sencha Cmd automatically creates a "Local Repository" for caching packages as well as for publishing packages. The role of the local repository for package authoring is not discussed in this guide. For details on that topic see Creating Sencha Cmd Packages.

Local Repository

Many operations implicitly use the local repository. Sencha Cmd follows these basic steps when it encounters the requires statement in "app.json":

  • Look in the workspace to see if the package is already present.
  • Check the local repository to see if there is a version already downloaded.
  • Look at the set of remote repositories defined to see if any has the package.
  • Download the package from the remote repository and add to the local repository.

Once the package has been downloaded, subsequent requirements for this package will not require downloading; the package will be found in the local repository.

Location of the Local Repository

The local repository is created in a folder "beside" the various versions to facilitate caching. For example, the default install directory of Sencha Cmd on Windows for user Foo might be something like this:


Given that install directory, the local repository would be located at:


This can be changed by editing the "sencha.cfg" in the Sencha Cmd install folder.

The contents of the local repository are discussed further in Creating Sencha Cmd Packages.

Remote Repositories

In order to download packages to the local repository, Sencha Cmd must know about remote repositories. By default, Sencha Cmd automatically adds the Sencha Package Repository as a remote repository named "sencha".

To see the list of remote repositories, run the sencha repository list command:

> sencha repository list
[INF] Remote repository connections (1):
[INF]     sencha -

You can add and remove repositories from this list using sencha repository add and sencha repository remove commands. Your local repository is in fact a valid remote repository for others if you chose to host it. For details on this, see Creating Sencha Cmd Packages.

The Package Catalog

The set of packages available to use is listed in the "catalog". You can display the contents of the global catalog using this command:

sencha package list

When you list packages you will notice that the listing includes names and versions.

Name Assignment

Because Sencha Cmd's repository management is distributed and you can add or remove remote repositories as you see fit, there is no Universal namespace of packages. If you retain the default "sencha" connection to the Sencha Package Repository, then you can view the content of that repository as a naming standard.

Packages published by Sencha (not included inside a Sencha Framework) will use names of the following forms:

  • sencha-*
  • ext-*
  • touch-*
  • cmd-*

All package names beginning with the above prefixes are reserved by Sencha with respect to the Sencha Package Repository. It is recommended that you avoid conflicting with these names even if you disconnect from the Sencha Package Repository.

Version Management

To connect packages and their consumers (that is, applications or other packages), it is important to consider the versions involved. To help manage this, all packages have version numbers which are used by the requires statement to handle version restrictions.

Package Versions

All packages are described by the combination of their name and their version. For each version of a package, however, there is another version number that describes its level of backwards compatibility. This version is a statement made by the package creator that they believe the particular version of their package to be backwards compatible to some specific previous version level.

In the "package.json" descriptor there are two important properties: version and compatVersion. For example:

    "version": "n.n.n",
    "compatVersion": "2.4.2",

This number must be of this format:


Version Restrictions

When using the requires property above we only specified the package name to keep the example as simple as possible. What that means precisely is "the latest version". In some cases this is acceptable, but it can be a risky requirement should that package's next release be a complete redesign and offer no level of backwards compatibility.

To protect your application from this, we can change the require statement to be very restrictive and lock down the version number we want:

    "name": "MyApp",
    "requires": [
        "[email protected]"

This approach has its place, but it prevents even maintenance releases of the package from being picked up. In final stages of a project, this may be exactly what is desired, but during development perhaps we want to be a little less restrictive and accept any compatible version.

The following change will do that:

    "name": "MyApp",
    "requires": [
        "[email protected]?"

The above requests the latest available version of "ext-easy-button" that has described itself as backwards compatible with version 1.0.

Other ways to restrict version matching are:

  • -1.2 (no lower limit - up to version 1.2)
  • 1.0- (no upper limit - version 1.0 or higher)
  • 1.0+ (same as above - version 1.0 or higher)
  • 1.0-1.2 (versions 1.0 up to 1.2 inclusive)
  • 1.0-1.2? (compatible with versions 1.0 up to 1.2 inclusive)

Resolving Versions

Given all of the desired and available versions, Sencha Cmd will determine the best set of matching packages and ensure that these are in your workspace.

If there are mutually exclusive requirements this process may fail. In this case, you will see an error message explaining what requirements could not be satisfied.