Dispatching events

dispatchEvent(eventObj)

private var dispatchEvent:Function;

var eventObj = new Object();
eventObj.type = "myEvent";
eventObj.target = this;
dispatchEvent(eventObj);

ancestorSlide.dispatchEvent({type:"revealChild", target:this});

Comments

murk379 said on Oct 10, 2004 at 8:51 PM :

I found that even when inheriting from UIComponent it was still necessary to import mx.events.EventDispatcher and call EventDispatcher.initialize(this) in my constructor to dispatch custom events.

Perhaps this indicates a problem with my code, but if not this should really be added to the docs.

larsendaniel said on Oct 31, 2004 at 12:02 AM :

i had no problem getting this to work. once i figured it out, it is quite simple! this is all it takes to get it to work:

[Event("newRandomEvent")]
class myComponent extends UIComponent {
.....
//place this in your code where you want it to fire.
dispatchEvent({type:"newRandomEvent"});
.....
}

the biggest hold up for me was that i was out of scope for a while. so if you are in the definition of a function on a button, you might have to do something like this:
this._parent.dispatchEvent({type:"newRandomEvent"}); //where this points to the button
in my case i was in another listener on an object in my component, so i had to say:
eventObj.target._parent.dispatchEvent({type:"newRandomEvent"});

in other words, the dispatchEvent is ON the component itself, make sure that is where you call it from.

good luck to all!

No screen name said on Dec 18, 2004 at 7:21 PM :

I had a tricky time getting anything to work. BUT lets have you learn from my trails. I (finally) got the check mark to say: "No errors!"

I had to include these items:

import Subject.as; //my custom subject definition
import mx.core.UIComponent; //Trial 1
import mx.events.EventDispatcher; //someone suggested this!
import mx.events.UIEvent; //website said this!

[event("ResponseReady")] // website said this too!

class SubjectAcquisition{
public var vSubject:Subject;

function SubjectAcquisition(SubjID:String, URL:String){
EventDispatcher.initialize(this); //some guys comments said that!
var vvSubject:Subject;
vSubject = vvSubject;
}
function Request(){
_parent.dispatchEvent({type:"ResponseReady", target:this});
//NOTE: SubjectAcquisition.dispatchEvent... DID NOT WORK. _parent finally did..
//It keeps saying "dispatchEvent is Not a method
}
}

Fallfish said on Jan 13, 2005 at 1:50 AM :

That's because you didn't extend UIObject or UIComponent.
Of course, you don't have to do so just for direct use of dispatchEvent call.
When not extending UIObject or UIComponent(or their subclasses), try the following:
import Subject.as; //my custom subject definition
import mx.events.EventDispatcher; //someone suggested this!

[event("ResponseReady")] // website said this too!

class SubjectAcquisition{
public var vSubject:Subject;
//--------------------------------------
//just define empty functions here
function dispatchEvent() {};
function addEventListener() {};
function removeEventListener() {};
//--------------------------------------

function SubjectAcquisition(SubjID:String, URL:String){
EventDispatcher.initialize(this); //some guys comments said that!
var vvSubject:Subject;
vSubject = vvSubject;
}
function Request(){
dispatchEvent({type:"ResponseReady", target:this});
}
}
//
Hope it works for you.
Good luck!

No screen name said on Jun 2, 2005 at 5:54 AM :

For larsendaniel and other people who've noticed that their events are fired within the scope of the child object (for example, a button component) rather than the base component class, there is a better way than saying this._parent.dispatchEvent({type:"newRandomEvent"})

You can use an event delegate to define the object scope that you want the event dispatcher to send the event to, something like:

myButton.dispatchEvent({"click", Delegate.create(this, checkFields)});

In the above case, if this were placed on a button, the "click" event would be sent to the calling class (this) rather than myButton. More info on this can be found in the actionscript dictionary under "delegates", or at http://actionscript-toolbox.com/sampleemail_mx.php

jepo said on Jun 9, 2005 at 2:41 PM :

Thank you for your comments. This site is for documentation feedback only. Some comments with general questions about how to use components, bug reports, or feature requests for the Flash product, have been removed. Please use the Flash webforums for questions about how to use components: http://webforums.macromedia.com/flash. Please use this form for feature requests or suspected bugs: www.macromedia.com/support/email/wishform/.

www_amirrocker_de said on Sep 1, 2005 at 7:17 AM :

Why can I only catch events at root level ? I dispatch an event in a label class
and if i add a Eventlistener on root > file it works I get the event
however if i wish to handle it inside a class i just dont seem to receive it .

Where is my mistake ?

<code>
// this clas is supposed to receive
import mx.events.*;
class LoginManager {
//var className:Function = de.allmediastreams.application.login.LoginManager;
//var symbol:String = "LogInWindow";

var addEventListener:Function;
var removeEventListener:Function;
var dispatchEvent:Function;
//var dispatchQueue:Function;

/** the grafical members */
private var _userMailInputLabel:TextField;
private var _userPasswordInput:TextField;
private var _doLoginButton:MovieClip;
private var _cancelLoginButton:MovieClip;

function LoginManager() {
trace("loginManager constructed > but not inited");
EventDispatcher.initialize(this);
init();
}

function init():Void {
_userMailInputLabel.addEventListener("onChanged", Delegate.create(this, inputHandler));

}

function inputHandler(evt){
trace("evt.target: "+evt.target);
}


}//end LoginManager

// the sending class
import mx.events.*;
class InputLabel {

var addEventListener:Function;
var removeEventListener:Function;
var dispatchEvent:Function;
//var dispatchQueue:Function;

private var _ilabel:TextField;

function InputLabel() {
trace("InputLabel constructed");
EventDispatcher.initialize(this);
init();
handleTextFieldEvents();
}

function init() {
//some init
}

private function handleTextFieldEvents():Void {
_ilabel.onChanged = function(evt) {
this._parent.onChanged(evt);
}

}
function onChanged(evt){
//trace("evt: "+evt);
//trace("_label changed event in InputLabel received");
dispatchEvent({type:"onChanged", target:evt});
}

}//end class
</code>

It doesnt get any simpler but it still doesnt work > do I have to extend MovieClip or Object explicitly and call super() ?

Please help ...
thanx
amir

No screen name said on Sep 12, 2005 at 4:31 AM :

this works out very well, no complex coding!! easy GO!

import mx.core.UIComponent;
import mx.events.*;
class MyBtn_cls extends UIComponent {
private var dispatchEvent:Function;
//------------------------------------------------------
public function init() {
super.init();
mx.events.EventDispatcher.initialize(this);
}
//------------------------------------------------------

public function draw() {
super.draw();
Bounding_box_mc._visible = false;
}
//------------------------------------------------------
function onRelease() {
dispatchEvent({type:"pressCheyi"});
}
//------------------------------------------------------
}


Enjoy!