Ext.util.DelayedTask
Hierarchy
Ext.BaseExt.util.DelayedTaskFiles
The DelayedTask class provides a convenient way to "buffer" the execution of a method, performing setTimeout where a new timeout cancels the old timeout. When called, the task will wait the specified time period before executing. If durng that time period, the task is called again, the original call will be cancelled. This continues so that the function is only called a single time for each iteration.
This method is especially useful for things like detecting whether a user has finished typing in a text field. An example would be performing validation on a keypress. You can use this class to buffer the keypress events for a certain number of milliseconds, and perform only if they stop for that amount of time.
Using Ext.util.DelayedTask is very simple:
//create the delayed task instance with our callback
var task = Ext.create('Ext.util.DelayedTask', function() {
console.log('callback!');
});
task.delay(1500); //the callback function will now be called after 1500ms
task.cancel(); //the callback function will never be called now, unless we call delay() again
Example
//create a textfield where we can listen to text
var field = Ext.create('Ext.field.Text', {
xtype: 'textfield',
label: 'Length: 0'
});
//add the textfield into a fieldset
Ext.Viewport.add({
xtype: 'formpanel',
items: [{
xtype: 'fieldset',
items: [field],
instructions: 'Type into the field and watch the count go up after 500ms.'
}]
});
//create our delayed task with a function that returns the fields length as the fields label
var task = Ext.create('Ext.util.DelayedTask', function() {
field.setLabel('Length: ' + field.getValue().length);
});
// Wait 500ms before calling our function. If the user presses another key
// during that 500ms, it will be cancelled and we'll wait another 500ms.
field.on('keyup', function() {
task.delay(500);
});
Available since: 1.1.0
Config options
Properties
Instance Properties Get the reference to the current class from which this object was instantiated. ...Get the reference to the current class from which this object was instantiated. Unlike statics,
this.self is scope-dependent and it's meant to be used for dynamic inheritance. See statics
for a detailed comparison
Ext.define('My.Cat', {
statics: {
speciesName: 'Cat' // My.Cat.speciesName = 'Cat'
},
constructor: function() {
alert(this.self.speciesName); / dependentOL 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'
Available since: 2.0.0
Get the reference to the current class from which this object was instantiated. Unlike statics,
this.self is scope-dependent and it's meant to be used for dynamic inheritance. See statics
for a detailed comparison
Ext.define('My.Cat', {
statics: {
speciesName: 'Cat' // My.Cat.speciesName = 'Cat'
},
constructor: function() {
alert(this.self.speciesName); / dependentOL 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'
Available since: 2.0.0
Static Properties
Methods
Instance Methods The parameters to this constructor serve as defaults and are not required. ...The parameters to this constructor serve as defaults and are not required.
Available since: 1.1.0
Parameters
- fn : Function
The default function to call.
- scope : Object
The default scope (The this reference) in which the function is called. If
not specified, this will refer to the browser window.
- args : Array
The default Array of arguments.
Returns
Call the original method that was previously overridden with override
Ext.define('My.Cat', {
constructor: functi...Call the original method that was previously overridden with 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!");
var instance = this.callOverridden();
alert("Meeeeoooowwww");
return instance;
}
});
var kitty = new My.Cat(); // alerts "I'm going to be a cat!"
// alerts "I'm a cat!"
// alerts "Meeeeoooowwww"
Available since: 2.0.0
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
Call the "parent" method of the current method. ...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 methods.
Ext.define('My.Derived2', {
extend: 'My.Base',
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',
statics: {
method: function (x) {
return this.callParent([x*2]); // calls My.Derived2.method
}
}
});
alert(My.Derived2.method(10); // now alerts 40
Available since: 2.0.0
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
delay( delay, newFn, newScope, newArgs )Cancels any pending timeout and queues a new one. ...Cancels any pending timeout and queues a new one.
Available since: 1.1.0
Parameters
- delay : Number
The milliseconds to delay
- newFn : Function
Overrides the original function passed when instantiated.
- newScope : Object
Overrides the original scope passed when instantiated. Remember that if no scope
is specified, this will refer to the browser window.
- newArgs : Array
Overrides the original args passed when instantiated.
destroy( )private ...
Available since: 2.0.0
Overrides: Ext.mixin.Observable.destroy, Ext.Container.destroy
getInterval( ) : Object Initialize configuration for this class. ...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'
Available since: 2.0.0
Parameters
- instanceConfig : Object
Returns
- Object
mixins The mixin prototypes as key - value pairs
onConfigUpdate( names, callback, scope )private setArgs( args ) setDelay( delay ) setFn( fn ) setInterval( interval ) setScope( scope ) Get the reference to the class from which this object was instantiated. ...Get the reference to the class from which this object was instantiated. Note that unlike 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
Available since: 2.0.0
Returns
updateInterval( newInterval, oldInterval )private
The parameters to this constructor serve as defaults and are not required.
Available since: 1.1.0
Parameters
- fn : Function
The default function to call.
- scope : Object
The default scope (The
thisreference) in which the function is called. If not specified,thiswill refer to the browser window. - args : Array
The default Array of arguments.
Returns
Call the original method that was previously overridden with 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!");
var instance = this.callOverridden();
alert("Meeeeoooowwww");
return instance;
}
});
var kitty = new My.Cat(); // alerts "I'm going to be a cat!"
// alerts "I'm a cat!"
// alerts "Meeeeoooowwww"
Available since: 2.0.0
Parameters
- args : Array/Arguments
The arguments, either an array or the
argumentsobject from the current method, for example:this.callOverridden(arguments)
Returns
- Object
Returns the result of calling the overridden method
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 methods.
Ext.define('My.Derived2', {
extend: 'My.Base',
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',
statics: {
method: function (x) {
return this.callParent([x*2]); // calls My.Derived2.method
}
}
});
alert(My.Derived2.method(10); // now alerts 40
Available since: 2.0.0
Parameters
- args : Array/Arguments
The arguments, either an array or the
argumentsobject from the current method, for example:this.callParent(arguments)
Returns
- Object
Returns the result of calling the parent method
Cancels any pending timeout and queues a new one.
Available since: 1.1.0
Parameters
- delay : Number
The milliseconds to delay
- newFn : Function
Overrides the original function passed when instantiated.
- newScope : Object
Overrides the original
scopepassed when instantiated. Remember that if no scope is specified,thiswill refer to the browser window. - newArgs : Array
Overrides the original
argspassed when instantiated.
Available since: 2.0.0
Overrides: Ext.mixin.Observable.destroy, Ext.Container.destroy
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'
Available since: 2.0.0
Parameters
- instanceConfig : Object
Returns
- Object
mixins The mixin prototypes as key - value pairs
Get the reference to the class from which this object was instantiated. Note that unlike 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
Available since: 2.0.0
Returns
Static Methods addConfig( config, fullMerge )privatestatic addMember( name, member )chainableprivatestatic addMembers( members )chainablestaticAdd methods / properties to the prototype of this class. ...Add methods / properties to the prototype of this class.
Ext.define('My.awesome.Cat', {
constructor: function() {
...
}
});
My.awesome.Cat.implement({
meow: function() {
alert('Meowww...');
}
});
var kitty = new My.awesome.Cat;
kitty.meow();
Available since: 2.0.0
Parameters
- members : Object
Add / override static properties of this class. ...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() { ... };
});
Available since: 2.0.0
Parameters
- members : Object
Returns
- Ext.Base
this
Borrow another class' members to the prototype of this class. ...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 '$$$$$$$'
Available since: 2.0.0
Parameters
- fromClass : Ext.Base
The class to borrow members from
- members : Array/String
The names of the members to borrow
Returns
- Ext.Base
this
Create a new instance of this Class. ...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.
Available since: 2.0.0
Returns
- Object
the created instance.
createAlias( alias, origin )staticCreate aliases for existing prototype methods. ...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()
Available since: 2.0.0
Parameters
- alias : String/Object
The new method name, or an object to set multiple aliases. See
flexSetter
- origin : String/Object
The original method name
Get the current class' name in string format. ...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'
Available since: 2.0.0
Returns
- String
className
mixin( name, mixinClass )privatestatic onExtended( fn, scope )chainableprivatestatic Override members of this class. ...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!");
var instance = this.callParent(arguments);
alert("Meeeeoooowwww");
return instance;
}
});
var kitty = new My.Cat(); // alerts "I'm going to be a cat!"
// alerts "I'm a cat!"
// alerts "Meeeeoooowwww"
As of 4.1, direct use of this method is deprecated. Use Ext.define
instead:
Ext.define('My.CatOverride', {
override: 'My.Cat',
constructor: function() {
alert("I'm going to be a cat!");
var instance = this.callParent(arguments);
alert("Meeeeoooowwww");
return instance;
}
});
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).
This method has been deprecated since 4.1.0
Please use Ext.define instead
Available since: 2.0.0
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
Add methods / properties to the prototype of this class.
Ext.define('My.awesome.Cat', {
constructor: function() {
...
}
});
My.awesome.Cat.implement({
meow: function() {
alert('Meowww...');
}
});
var kitty = new My.awesome.Cat;
kitty.meow();
Available since: 2.0.0
Parameters
- members : Object
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() { ... };
});
Available since: 2.0.0
Parameters
- members : Object
Returns
- Ext.Base
this
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 '$$$$$$$'
Available since: 2.0.0
Parameters
- fromClass : Ext.Base
The class to borrow members from
- members : Array/String
The names of the members to borrow
Returns
- Ext.Base
this
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.
Available since: 2.0.0
Returns
- Object
the created instance.
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()
Available since: 2.0.0
Parameters
- alias : String/Object
The new method name, or an object to set multiple aliases. See flexSetter
- origin : String/Object
The original method name
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'
Available since: 2.0.0
Returns
- String
className
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!");
var instance = this.callParent(arguments);
alert("Meeeeoooowwww");
return instance;
}
});
var kitty = new My.Cat(); // alerts "I'm going to be a cat!"
// alerts "I'm a cat!"
// alerts "Meeeeoooowwww"
As of 4.1, direct use of this method is deprecated. Use Ext.define instead:
Ext.define('My.CatOverride', {
override: 'My.Cat',
constructor: function() {
alert("I'm going to be a cat!");
var instance = this.callParent(arguments);
alert("Meeeeoooowwww");
return instance;
}
});
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).
This method has been deprecated since 4.1.0
Please use Ext.define instead
Available since: 2.0.0
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