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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
protected

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.

Parameters

item :  Object

The config object being added.

Returns
Ext.Component

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 6.2.1 - Modern Toolkit


top

Hierarchy

Ext.Base
Ext.Mixin
Ext.mixin.Inheritable

Mixed Into

Ext.Widget

NOTE: This is a private utility class for internal use by the framework. Don't rely on its existence.

Summary

A mixin that provides the functionality for inheritable configs. This allows linking components and containers via a prototype-chained object for accessing inherited values.

Getting Inherited Properties

A component's inherited state is used to keep track of aspects of a component's state that might be influenced by its ancestors like "collapsed" and "hidden". For example:

 var hidden = this.getInheritedConfig('hidden');

The above will produce true if this or any ancestor component has its hidden config set to true.

Chained Objects

Inheritable properties are implemented by chaining each component's inherited state object to its parent container's inherited state object via the prototype. The result is such that if a component's inheritedState does not have it's own property, it inherits the property from the nearest ancestor that does.

In the case of a Container, two state objects are created. The primary ("outer") object is used for reading inherited properties. It is also what a child will prototype chain to if that child is not part of the container's items collection. Anything in the items collection will chain to the inheritedStateInner object instead. This object is prototype chained to inheritedState but allows for Container's layout to set inherited properties that specifically apply only to children of the container. This inner object is unlikely to be needed by user code.

Publishing Inherited Properties

The first step to publishing inherited properties is to override initInheritedState and add properties that have inheritable values.

 initInheritedState: function (inheritedState) {
     this.callParent(arguments);

     if (this.getHidden()) {
         inheritedState.hidden = true;
     }
 }

The above is important because initInheritedState is called whenever the object needs to be repopulated. As you can see, only true values are added to inheritedState in this case because false would mask a hidden value of true from an ancestor.

If these values change dynamically, these properties must be maintained. For example:

 updateHidden: function (hidden) {
     var inherited = this.getInherited();

     if (hidden) {
         inherited.hidden = true;
     } else {
         // Unmask whatever may be inherited:
         delete inherited.hidden;
     }
 }

Proper Usage

ALWAYS access inherited state using getInherited or getInheritedConfig, not by accessing inheritedState directly.

The inheritedState property does not exist until the first call to getInherited. At that point getInherited walks up the component tree to establish the inheritedState prototype chain. Additionally the inheritedState property should NOT be relied upon even after the initial call to getInherited because it is possible for it to become invalid.

Invalidation typically happens when a component is moved to a new container. In such a case the inheritedState remains invalid until the next time getInherited is called on the component or one of its descendants.

No members found using the current filters

properties

Instance Properties

$className
private pri

Defaults to:

'Ext.Base'

$configPrefixed : Boolean
private pri

The value true causes config values to be stored on instances using a property name prefixed with an underscore ("_") character. A value of false stores config values as properties using their exact name (no prefix).

Defaults to:

true

Available since: 5.0.0

$configStrict : Boolean
private pri

The value true instructs the initConfig method to only honor values for properties declared in the config block of a class. When false, properties that are not declared in a config block will be placed on the instance.

Defaults to:

true

Available since: 5.0.0

clearPropertiesOnDestroy : Boolean / "async"
protected pro

Setting this property to false will prevent nulling object references on a Class instance after destruction. Setting this to "async" will delay the clearing for approx 50ms.

Defaults to:

true

Available since: 6.2.0

clearPrototypeOnDestroy : Boolean
private pri

Setting this property to true will result in setting the object's prototype to null after the destruction sequence is fully completed. After that, most attempts at calling methods on the object instance will result in "method not defined" exception. This can be very helpful with tracking down otherwise hard to find bugs like runaway Ajax requests, timed functions not cleared on destruction, etc.

Note that this option can only work in browsers that support Object.setPrototypeOf method, and is only available in debugging mode.

Defaults to:

false

Available since: 6.2.0

destroyed : Boolean
protected pro

This property is set to true after the destroy method is called.

Defaults to:

false

isConfiguring : Boolean
readonly ro protected pro

This property is set to true during the call to initConfig.

Defaults to:

false

Available since: 5.0.0

isFirstInstance : Boolean
readonly ro protected pro

This property is set to true if this instance is the first of its class.

Defaults to:

false

Available since: 5.0.0

isInstance : Boolean
readonly ro protected pro

This value is true and is used to identify plain objects from instances of a defined class.

Defaults to:

true

self : Ext.Class
protected pro

Get the reference to the current class from which this object was instantiated. Unlike Ext.Base#statics, this.self is scope-dependent and it's meant to be used for dynamic inheritance. See Ext.Base#statics for a detailed comparison

Ext.define('My.Cat', {
    statics: {
        speciesName: 'Cat' // My.Cat.speciesName = 'Cat'
    },

    constructor: function() {
        alert(this.self.speciesName); // dependent on 'this'
    },

    clone: function() {
        return new this.self();
    }
});


Ext.define('My.SnowLeopard', {
    extend: 'My.Cat',
    statics: {
        speciesName: 'Snow Leopard'         // My.SnowLeopard.speciesName = 'Snow Leopard'
    }
});

var cat = new My.Cat();                     // alerts 'Cat'
var snowLeopard = new My.SnowLeopard();     // alerts 'Snow Leopard'

var clone = snowLeopard.clone();
alert(Ext.getClassName(clone));             // alerts 'My.SnowLeopard'

Defaults to:

Base

Static Properties

$onExtended
static sta private pri

Defaults to:

[]

methods

Instance Methods

addDeprecations ( deprecations )
private pri

This method applies a versioned, deprecation declaration to this class. This is typically called by the deprecated config.

Parameters

deprecations :  Object

callOverridden ( args ) : Object
deprecated dep protected pro

Call the original method that was previously overridden with Ext.Base#override

Ext.define('My.Cat', {
    constructor: function() {
        alert("I'm a cat!");
    }
});

My.Cat.override({
    constructor: function() {
        alert("I'm going to be a cat!");

        this.callOverridden();

        alert("Meeeeoooowwww");
    }
});

var kitty = new My.Cat(); // alerts "I'm going to be a cat!"
                          // alerts "I'm a cat!"
                          // alerts "Meeeeoooowwww"

Parameters

args :  Array/Arguments

The arguments, either an array or the arguments object from the current method, for example: this.callOverridden(arguments)

Returns

:Object

Returns the result of calling the overridden method

Deprecated since version 4.1.0

callParent ( args ) : Object
protected pro

Call the "parent" method of the current method. That is the method previously overridden by derivation or by an override (see Ext#define).

 Ext.define('My.Base', {
     constructor: function (x) {
         this.x = x;
     },

     statics: {
         method: function (x) {
             return x;
         }
     }
 });

 Ext.define('My.Derived', {
     extend: 'My.Base',

     constructor: function () {
         this.callParent([21]);
     }
 });

 var obj = new My.Derived();

 alert(obj.x);  // alerts 21

This can be used with an override as follows:

 Ext.define('My.DerivedOverride', {
     override: 'My.Derived',

     constructor: function (x) {
         this.callParent([x*2]); // calls original My.Derived constructor
     }
 });

 var obj = new My.Derived();

 alert(obj.x);  // now alerts 42

This also works with static and private methods.

 Ext.define('My.Derived2', {
     extend: 'My.Base',

     // privates: {
     statics: {
         method: function (x) {
             return this.callParent([x*2]); // calls My.Base.method
         }
     }
 });

 alert(My.Base.method(10));     // alerts 10
 alert(My.Derived2.method(10)); // alerts 20

Lastly, it also works with overridden static methods.

 Ext.define('My.Derived2Override', {
     override: 'My.Derived2',

     // privates: {
     statics: {
         method: function (x) {
             return this.callParent([x*2]); // calls My.Derived2.method
         }
     }
 });

 alert(My.Derived2.method(10); // now alerts 40

To override a method and replace it and also call the superclass method, use method-callSuper. This is often done to patch a method to fix a bug.

Parameters

args :  Array/Arguments

The arguments, either an array or the arguments object from the current method, for example: this.callParent(arguments)

Returns

:Object

Returns the result of calling the parent method

callSuper ( args ) : Object
protected pro

This method is used by an override to call the superclass method but bypass any overridden method. This is often done to "patch" a method that contains a bug but for whatever reason cannot be fixed directly.

Consider:

 Ext.define('Ext.some.Class', {
     method: function () {
         console.log('Good');
     }
 });

 Ext.define('Ext.some.DerivedClass', {
     extend: 'Ext.some.Class',

     method: function () {
         console.log('Bad');

         // ... logic but with a bug ...

         this.callParent();
     }
 });

To patch the bug in Ext.some.DerivedClass.method, the typical solution is to create an override:

 Ext.define('App.patches.DerivedClass', {
     override: 'Ext.some.DerivedClass',

     method: function () {
         console.log('Fixed');

         // ... logic but with bug fixed ...

         this.callSuper();
     }
 });

The patch method cannot use method-callParent to call the superclass method since that would call the overridden method containing the bug. In other words, the above patch would only produce "Fixed" then "Good" in the console log, whereas, using callParent would produce "Fixed" then "Bad" then "Good".

Parameters

args :  Array/Arguments

The arguments, either an array or the arguments object from the current method, for example: this.callSuper(arguments)

Returns

:Object

Returns the result of calling the superclass method

destroy

This method is called to cleanup an object and its resources. After calling this method, the object should not be used any further in any way, including access to its methods and properties.

To prevent potential memory leaks, all object references will be nulled at the end of destruction sequence, unless clearPropertiesOnDestroy is set to false.

fixReference
private pri

Sets up a reference on our current reference holder.

getConfig ( [name], [peek] ) : Object

Returns a specified config property value. If the name parameter is not passed, all current configuration options will be returned as key value pairs.

Parameters

name :  String (optional)

The name of the config property to get.

peek :  Boolean (optional)

true to peek at the raw value without calling the getter.

Defaults to: false

Returns

:Object

The config property value.

getInherited ( [inner] ) : Object

This method returns an object containing the inherited properties for this instance.

Available since: 5.0.0

Parameters

inner :  Boolean (optional)

Pass true to return inheritedStateInner instead of the normal inheritedState object. This is only needed internally and should not be passed by user code.

Defaults to: false

Returns

:Object

The inheritedState object containing inherited properties.

getInheritedConfig ( property, [skipThis] ) : Mixed

This method returns the value of a config property that may be inherited from some ancestor.

In some cases, a config may be explicitly set on a component with the intent of only being presented to its children while that component should act upon the inherited value (see referenceHolder for example). In these cases the skipThis parameter should be specified as true.

Available since: 5.0.0

Parameters

property :  String

The name of the config property to return.

skipThis :  Boolean (optional)

Pass true if the property should be ignored if found on this instance. In other words, true means the property must be inherited and not explicitly set on this instance.

Defaults to: false

Returns

:Mixed

The value of the requested property.

getInitialConfig ( [name] ) : Object/Mixed

Returns the initial configuration passed to the constructor when instantiating this class.

Given this example Ext.button.Button definition and instance:

Ext.define('MyApp.view.Button', {
    extend: 'Ext.button.Button',
    xtype: 'mybutton',

    scale: 'large',
    enableToggle: true
});

var btn = Ext.create({
    xtype: 'mybutton',
    renderTo: Ext.getBody(),
    text: 'Test Button'
});

Calling btn.getInitialConfig() would return an object including the config options passed to the create method:

xtype: 'mybutton',
renderTo: // The document body itself
text: 'Test Button'

Calling btn.getInitialConfig('text')returns 'Test Button'.

Parameters

name :  String (optional)

Name of the config option to return.

Returns

:Object/Mixed

The full config object or a single config value when name parameter specified.

getRefOwner
protected pro

Used by Ext.ComponentQuery, and the up method to find the owning Component in the linkage hierarchy.

By default this returns the Container which contains this Component.

This may be overridden by Component authors who implement ownership hierarchies which are not based upon ownerCt, such as BoundLists being owned by Fields or Menus being owned by Buttons.

hasConfig ( name )
private pri

Parameters

name :  String

initConfig ( instanceConfig ) : Ext.Base
chainable ch protected pro

Initialize configuration for this class. a typical example:

Ext.define('My.awesome.Class', {
    // The default config
    config: {
        name: 'Awesome',
        isAwesome: true
    },

    constructor: function(config) {
        this.initConfig(config);
    }
});

var awesome = new My.awesome.Class({
    name: 'Super Awesome'
});

alert(awesome.getName()); // 'Super Awesome'

Parameters

instanceConfig :  Object

Returns

:Ext.Base

this

initInheritedState ( inheritedState, [inheritedStateInner] )
protected pro

This method is called to initialize the inheritedState objects for this instance. This amounts to typically copying certain properties from the instance to the given object.

Available since: 5.0.0

Parameters

inheritedState :  Object

The state object for this instance.

inheritedStateInner :  Object (optional)

This object is only provided for containers.

invalidateInheritedState
private pri

This method marks the current inherited state as invalid. The next time a call is made to getInherited the objects will be recreated and initialized.

Available since: 5.0.0

lookupReferenceHolder ( [skipThis] ) : Ext.app.ViewController/Ext.Container
private pri

Gets the Controller or Component that is used as the reference holder for this view.

Available since: 5.0.0

Parameters

skipThis :  Boolean (optional)

false to return this as the reference holder if this instance has set referenceHolder. Unlike getInheritedConfig this method defaults to true because it is possible that a reference property set by the owner of a component that is also a referenceHolder itself. In this case, the reference connects not to this component but to the parent referenceHolder.

Defaults to: true

Returns

:Ext.app.ViewController/Ext.Container

The reference holder.

onInheritedAdd ( instanced )
private pri

Called when this Inheritable is added to a parent

Parameters

instanced :  Boolean

onInheritedRemove ( destroying )
private pri

Called when this inheritable is removed from a parent

Parameters

destroying :  Boolean

true if this item will be destroyed by it's container

resolveListenerScope ( [defaultScope] ) : Ext.app.ViewController/Ext.Container
protected pro

Gets the Controller or Component that is used as the event root for this view.

Available since: 5.0.0

Parameters

defaultScope :  Object (optional)

The default scope to return if none is found.

Defaults to: this

Returns

:Ext.app.ViewController/Ext.Container

The default listener scope.

resolveSatelliteListenerScope ( satellite, [defaultScope] ) : Object
protected pro

Returns the default listener scope for a "satellite" of this component. Used for resolving scope for observable objects that are not part of the normal Container/Component hierarchy (for example, plugins)

Available since: 5.1.1

Parameters

satellite :  Ext.mixin.Observable

defaultScope :  Object (optional)

Returns

:Object

The listener scope

setConfig ( name, [value] ) : Ext.Base
chainable ch

Sets a single/multiple configuration options.

Parameters

name :  String/Object

The name of the property to set, or a set of key value pairs to set.

value :  Object (optional)

The value to set for the name parameter.

Returns

:Ext.Base

this

statics Ext.Class
protected pro

Get the reference to the class from which this object was instantiated. Note that unlike Ext.Base#self, this.statics() is scope-independent and it always returns the class from which it was called, regardless of what this points to during run-time

Ext.define('My.Cat', {
    statics: {
        totalCreated: 0,
        speciesName: 'Cat' // My.Cat.speciesName = 'Cat'
    },

    constructor: function() {
        var statics = this.statics();

        alert(statics.speciesName);     // always equals to 'Cat' no matter what 'this' refers to
                                        // equivalent to: My.Cat.speciesName

        alert(this.self.speciesName);   // dependent on 'this'

        statics.totalCreated++;
    },

    clone: function() {
        var cloned = new this.self();   // dependent on 'this'

        cloned.groupName = this.statics().speciesName;   // equivalent to: My.Cat.speciesName

        return cloned;
    }
});


Ext.define('My.SnowLeopard', {
    extend: 'My.Cat',

    statics: {
        speciesName: 'Snow Leopard'     // My.SnowLeopard.speciesName = 'Snow Leopard'
    },

    constructor: function() {
        this.callParent();
    }
});

var cat = new My.Cat();                 // alerts 'Cat', then alerts 'Cat'

var snowLeopard = new My.SnowLeopard(); // alerts 'Cat', then alerts 'Snow Leopard'

var clone = snowLeopard.clone();
alert(Ext.getClassName(clone));         // alerts 'My.SnowLeopard'
alert(clone.groupName);                 // alerts 'Cat'

alert(My.Cat.totalCreated);             // alerts 3

Returns

:Ext.Class
Static Methods

addConfig ( config, [mixinClass] )
static sta private pri

Adds new config properties to this class. This is called for classes when they are declared, then for any mixins that class may define and finally for any overrides defined that target the class.

Parameters

config :  Object

mixinClass :  Ext.Class (optional)

The mixin class if the configs are from a mixin.

addInheritableStatics ( members ) :
chainable ch static sta private pri

Parameters

members :  Object

Returns

:

addMember ( name, member ) :
chainable ch static sta private pri

Parameters

name :  Object

member :  Object

Returns

:

addMembers ( members, [isStatic], [privacy] ) :
chainable ch static sta

Add methods / properties to the prototype of this class.

Ext.define('My.awesome.Cat', {
    constructor: function() {
        ...
    }
});

 My.awesome.Cat.addMembers({
     meow: function() {
        alert('Meowww...');
     }
 });

 var kitty = new My.awesome.Cat();
 kitty.meow();

Parameters

members :  Object

The members to add to this class.

isStatic :  Boolean (optional)

Pass true if the members are static.

Defaults to: false

privacy :  Boolean (optional)

Pass true if the members are private. This only has meaning in debug mode and only for methods.

Defaults to: false

Returns

:

addStatics ( members ) : Ext.Base
chainable ch static sta

Add / override static properties of this class.

Ext.define('My.cool.Class', {
    ...
});

My.cool.Class.addStatics({
    someProperty: 'someValue',      // My.cool.Class.someProperty = 'someValue'
    method1: function() { ... },    // My.cool.Class.method1 = function() { ... };
    method2: function() { ... }     // My.cool.Class.method2 = function() { ... };
});

Parameters

members :  Object

Returns

:Ext.Base

this

borrow ( fromClass, members ) : Ext.Base
static sta private pri

Borrow another class' members to the prototype of this class.

Ext.define('Bank', {
    money: '$$$',
    printMoney: function() {
        alert('$$$$$$$');
    }
});

Ext.define('Thief', {
    ...
});

Thief.borrow(Bank, ['money', 'printMoney']);

var steve = new Thief();

alert(steve.money); // alerts '$$$'
steve.printMoney(); // alerts '$$$$$$$'

Parameters

fromClass :  Ext.Base

The class to borrow members from

members :  Array/String

The names of the members to borrow

Returns

:Ext.Base

this

callParent ( args )
static sta protected pro

Parameters

args :  Object

callSuper ( args )
static sta protected pro

Parameters

args :  Object

create Object
static sta

Create a new instance of this Class.

Ext.define('My.cool.Class', {
    ...
});

My.cool.Class.create({
    someConfig: true
});

All parameters are passed to the constructor of the class.

Returns

:Object

the created instance.

createAlias ( alias, origin )
static sta

Create aliases for existing prototype methods. Example:

Ext.define('My.cool.Class', {
    method1: function() { ... },
    method2: function() { ... }
});

var test = new My.cool.Class();

My.cool.Class.createAlias({
    method3: 'method1',
    method4: 'method2'
});

test.method3(); // test.method1()

My.cool.Class.createAlias('method5', 'method3');

test.method5(); // test.method3() -> test.method1()

Parameters

alias :  String/Object

The new method name, or an object to set multiple aliases. See flexSetter

origin :  String/Object

The original method name

extend ( parentClass )
static sta private pri

Parameters

parentClass :  Object

getConfigurator Ext.Configurator
static sta private pri

Returns the Ext.Configurator for this class.

Returns

:Ext.Configurator

getName String
static sta

Get the current class' name in string format.

Ext.define('My.cool.Class', {
    constructor: function() {
        alert(this.self.getName()); // alerts 'My.cool.Class'
    }
});

My.cool.Class.getName(); // 'My.cool.Class'

Returns

:String

className

mixin ( name, mixinClass ) :
chainable ch static sta private pri

Used internally by the mixins pre-processor

Parameters

name :  Object

mixinClass :  Object

Returns

:

onExtended ( fn, scope ) :
chainable ch static sta private pri

Parameters

fn :  Object

scope :  Object

Returns

:

override ( members ) : Ext.Base
chainable ch static sta

Override members of this class. Overridden methods can be invoked via Ext.Base#callParent.

Ext.define('My.Cat', {
    constructor: function() {
        alert("I'm a cat!");
    }
});

My.Cat.override({
    constructor: function() {
        alert("I'm going to be a cat!");

        this.callParent(arguments);

        alert("Meeeeoooowwww");
    }
});

var kitty = new My.Cat(); // alerts "I'm going to be a cat!"
                          // alerts "I'm a cat!"
                          // alerts "Meeeeoooowwww"

Direct use of this method should be rare. Use Ext.define instead:

Ext.define('My.CatOverride', {
    override: 'My.Cat',
    constructor: function() {
        alert("I'm going to be a cat!");

        this.callParent(arguments);

        alert("Meeeeoooowwww");
    }
});

The above accomplishes the same result but can be managed by the Ext.Loader which can properly order the override and its target class and the build process can determine whether the override is needed based on the required state of the target class (My.Cat).

Parameters

members :  Object

The properties to add to this class. This should be specified as an object literal containing one or more properties.

Returns

:Ext.Base

this class

triggerExtended
static sta private pri

Ext JS 6.2.1 - Modern Toolkit