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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 7.8.0 - Modern Toolkit


top

NPM Package

@sencha/ext-core

Hierarchy

Ext.Base
Ext.util.LocalStorage

Summary

This class provides a common API to LocalStorage with backwards compatibility for IE.

The primary aspects of this API match the HTML5 standard API except that this class provides a scoping mechanism to isolate property values by instance. This scope is determined from the id property. Further, this class does not expose the number of keys in the store as a length property as this cannot be maintained reliably without undue cost. Instead there is a getKeys method that returns the cached array of keys which is lazily populated on first call.

For example:

 var store = new Ext.util.LocalStorage({
         id: 'foo'
     });

 store.setItem('bar', 'stuff');

 // Equivalent to:
 window.localStorage.setItem('foo-bar', 'stuff');

In all cases, the id property is only used by the underlying storage and should not be needed in item access calls or appear when enumerating keys.

To continue with the previous example:

 var keys = store.getKeys();
 console.log(keys.length);   // logs 1
 console.log(store.key(0));  // logs "bar"

Sharing Instances

The management of the underlying storage can be broken if multiple instances of this class are created with the same id simultaneously. To avoid creating multiple instances with the same id, use the get method and it will lazily create and share a single instance. When you are done with the shared instance, call release.

 var storage = Ext.util.LocalStorage.get('id');

 ...

 storage.release(); // do not call destroy as others may be using this object

IMPORTANT: Do not mix direction instantiation and get with the same id.

Legacy IE

Older IE browsers (specifically IE7 and below) do not support localStorage so this class provides equivalent support using the IE proprietary persistence mechanism: the userData behavior.aspx). In this mode, the id serves as name passed to the load and save methods and as the suffix on the DOM element added to the head.

In this mode, writes to the underlying storage are buffered and delayed for performance reasons. This can be managed using the flushDelay config or by directly calling the save method.

No members found using the current filters

configs

Optional Configs

id : String

The unique identifier for this store. This config is required to scope this storage distinctly from others. Ultimately, this is used to set a prefix on all keys.

Defaults to:

null

lazyKeys : Boolean

Determines if the keys collection is continuously maintained by this object. By default the keys array is lazily fetched from the underlying store and when keys are removed, the array is discarded. This heuristic tends to be safer than doing the linear removal and array rippling to remove keys from the array on each call to removeItem. If the cost of scanning localStorage for keys is high enough and if the keys are frequently needed, then this flag can be set to false to instruct this class to maintain the keys array once it has been determined.

Defaults to:

true

prefix : String

The prefix to apply to all localStorage keys manages by this instance. This does not apply to the legacy IE mechanism but only to the HTML5 localStorage keys. If not provided, the id property initializes this value with "id-".

Defaults to:

''

session : Boolean

Specify this as true to use sessionStorage instead of the default localStoreage. This option is not supported in legacy IE browsers (IE 6 and 7) and is ignored.

Defaults to:

false

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

$configTransforms : Object / Array
private pri

A prototype-chained object storing transform method names and priorities stored on the class prototype. On first instantiation, this object is converted into an array that is sorted by priority and stored on the constructor.

Defaults to:

{}

_keys : String[]
readonly ro private pri

The array of all key names. This will be null if the keys need to be redetermined by the getKeys method.

Defaults to:

null

_store
readonly ro private pri

The Storage instance used to store items. This is based on the session config.

Defaults to:

null

_users : Number
readonly ro private pri

The number of users that have requested this instance using the get method and have not yet called release.

Defaults to:

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
readonly ro

This property is set to true when the instance's 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:

[]

supported : Boolean
readonly ro static sta

This will be true if some form of local storage is supported or false if not.

Defaults to:

true

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
Use method-callParent instead.

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

clear

Removes all of the keys of this storage. NOTE: This method conforms to the standard HTML5 Storage interface.

destroy

Destroys this instance and for legacy IE, ensures data is flushed to persistent storage. This method should not be called directly on instances returned by the get method. Call release instead for such instances.

NOTE: For non-legacy IE browsers, there is no harm in failing to call this method. In legacy IE, however, failing to call this method can result in memory leaks.

destroyMembers ( args )

Destroys member properties by name.

If a property name is the name of a config, the getter is not invoked, so if the config has not been initialized, nothing will be done.

The property will be destroyed, and the corrected name (if the property is a config and config names are prefixed) will set to null in this object's dictionary.

Parameters

args :  String...

One or more names of the properties to destroy and remove from the object.

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

ifInitialized :  Boolean (optional)

true to only return the initialized property value, not the raw config value, and not to trigger initialization. Returns undefined if the property has not yet been initialized.

Defaults to: false

Returns

:Object

The config property value.

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.

getItem ( key ) : String

Returns the value associated with the given key. NOTE: This method conforms to the standard HTML5 Storage interface.

Parameters

key :  String

The key.

Returns

:String

The value associated with the given key.

getKeys String[]

Returns the keys for this storage.

Returns

:String[]

The keys for this storage. This array should be considered as readonly.

hasConfig ( name )
private pri

Parameters

name :  String

init
private pri

Initializes this instance.

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

key ( index ) : String

Returns the specified key given its index. These keys have the scoping prefix removed so they match what was passed to setItem. NOTE: This method conforms to the standard HTML5 Storage interface.

Parameters

index :  Number

The index of the desired key.

Returns

:String

The key.

release

Call this method when finished with an instance returned by get instead of calling destroy. When the last shared use of this instance calls release, the destroy method is called automatically.

NOTE: Failing to call this method will result in memory leaks.

removeItem ( key )

Removes the value associated with the given key. NOTE: This method conforms to the standard HTML5 Storage interface.

Parameters

key :  String

The key.

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

setItem ( key, value )

Sets the value associated with the given key. NOTE: This method conforms to the standard HTML5 Storage interface.

Parameters

key :  String

The key.

value :  String

The new associated value for key.

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();

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


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

        statics.totalCreated++;
    },

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

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

watchConfig ( name, fn, scope )
private pri

Watches config properties.

 instance.watchConfig({
     title: 'onTitleChange',
     scope: me
 });

Available since: 6.7.0

Parameters

name :  Object

fn :  Object

scope :  Object

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, privacy ) :
chainable ch static sta private pri

Parameters

name :  Object

member :  Object

privacy :  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

get ( id ) : Ext.util.LocalStorage
static sta

Returns a shared instance of the desired local store given its id. When you are finished with the returned object call the release method:

 var store = Ext.util.LocalStorage.get('foo');

 // .. use store

 store.release();

NOTE: Do not mix this call with direct instantiation of the same id.

Parameters

id :  String/Object

The id of the desired instance or a config object with an id property at a minimum.

Returns

:Ext.util.LocalStorage

The desired instance, created if needed.

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 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

save
static sta private pri

triggerExtended
static sta private pri

Ext JS 7.8.0 - Modern Toolkit