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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 6.2.0 - Classic Toolkit

Guide applies to: classic

Tablet and Touch-Screen Support in Ext JS 5

Ext JS offers support for devices withtouch-screen input, including tablets and touch-screen laptops. The primary goal of this feature is to allow Ext JS applications to run on touch-screen devices with little or no modification. This means that developers can spend less time thinking about compatibility issues, and more time implementing great applications.

How Touch-Screen Support is Implemented

Support for devices with touch-screens can be broken down into three categories.

Event Normalization

Event normalization is the key to allowing Ext JS applications to run on touch-screen devices. This normalization occurs behind the scenes and is a simple translation from standard mouse events to their equivalent touch and pointer events.

Pointer events are a w3c standard for dealing with events that target a specific set of coordinates on the screen, regardless of input device (mouse, touch, stylus, etc.)

When your code requests a listener for a mouse event, the framework attaches a similar touch or pointer event as needed. For example, if the application attempts to attach a mousedown listener:

myElement.on('mousedown', someFunction);

The event system translates this to touchstart in the case of a device that supports touch events:

myElement.on('touchstart', someFunction);

Or, pointerdown in the case of a device that supports pointer events:

myElement.on('pointerdown', someFunction);

This translation is in place so that you may achieve tablet and touch-screen support without any additional coding.

In most cases the framework can transition seamlessly between mouse, touch, and pointer input. However, there are a few mouse interactions (such as mouseover) that do not translate easily into touch interactions. Such events will need to be handled on an individual basis and are addressed in a following section.

Gesture System

In addition to standard DOM events, Elements also fire synthesized "gesture" events. Since the Sencha Touch event system forms the basis for the new event system in Ext JS 5, Sencha Touch users may already be familiar with this concept.

From a browser's perspective, there are 3 primary types of pointer, touch, and mouse events - start, move, and end:

Event Touch Pointer Mouse
Start touchstart pointerdown mousedown
Move touchmove pointermove mousemove
Stop touchend pointerup

Upon interpreting the sequence and timing of these events, the framework can synthesize more complex events such as drag, swipe, longpress, pinch, rotate, and tap. Ext JS applications can listen for gesture events just like any other event, for example:

Ext.get('myElement').on('longpress', handlerFunction);

The original Sencha Touch gesture system was designed primarily with touch events in mind. By adding full support for pointer and mouse events to the Gesture system, Ext JS allows any gesture to respond to any type of input. This means not only that all gestures can be triggered using touch input, but all single-point gestures (tap, swipe, etc.) can be triggered using a mouse as well. This results in a gesture system that works seamlessly across devices regardless of input type.

What Touch-Screen Support Means for Applications

Normalized events and gesture recognition are active by default in Ext JS applications. This means that, in most cases, no special actions are necessary to enable tablet and touch-screen support. However, there are two particular areas that may need special attention.

The first deals with mouse events that don't have an obvious analog in the touch world. As of now, Ext JS does not attempt to perform any normalization for the following mouse events:

  • mouseover
  • mouseout
  • mousenter
  • mouseleave

Application functionality that responds to these events on desktop devices may have to be re-implemented separately for touch devices. Developers should keep this in mind when architecting applications. In order to ensure that important application functionality is accessible to touch screens, it may be necessary to provide an alternate implementation for these interactions. This often means substituting the mouse event with an appropriate touch gesture. Ext JS takes this approach internally in several places.

One example is the grid component. On desktop devices, grid column header menus are shown in response to a click on the header's trigger element. However, the trigger only becomes visible in response to a mouseover of the column header. Since a gesture equivalent to 'mouseover' does not exist on touch screens, the trigger never becomes visible and so cannot be touched. To ensure that the column header menu can be accessed, Ext JS displays the menu in response to a 'longpress' if it detects that the grid is being used on a touch-screen device.

Note: Developers of applications and custom components may need to make similar adjustments as needed.

The second area that may require attention relates to some internal framework changes. In order to support Touch gestures, Ext JS 5+ switched to a delegated event model. Instead of attaching listeners directly to DOM elements, a single listener for each event type is attached at the top of the DOM (the window or document object). The Ext JS event system then dispatches event handlers based on the target elements of events that bubble up to the window object. Application developers who use only Ext JS APIs to listen for events will not experience any problems with this new approach.

However, if DOM APIs are used to directly attach listeners (addEventListener or attachEvent), or if 3rd party JavaScript libraries are used, issues may occur with the timing of directly attached event handlers relative to the timing of their delegated counterparts.

Note: Tablet and touch-screen support works with Safari, Chrome and IE10+. The Android browser is not supported.

Ext JS 6.2.0 - Classic Toolkit