6 Replies Latest reply on May 20, 2008 11:59 AM by otisme

    EVENTS in flex

    LoGicMaNia
      hi friends,
      I am developing an application just like FLEXSTORE sample application.But i don't get the eventDispatch in the sample. I have navigate through the source several times. But i don't get the idea. Please any one help me to put some light on it?.....

      regards
        • 1. Re: EVENTS in flex
          Gregory Lafrance Level 6
          I think you will need to clarify where you are seeing the problem.
          • 2. Re: EVENTS in flex
            LoGicMaNia Level 1
            hi,
            I got the problem in productCatalogueEvent.In their is function called "dispatchEvent";I doubtfull here.
            If this function is caled here where does it affect?
            I can't get wat will do wen this function called?

            regards
            • 3. Re: EVENTS in flex
              BaliHi
              I dont have your sample but Events are integral to Flex and it is something that is a bit different to most programming. Basically dispatching an event is sending information out to anything that is LISTENING to say that something has occurred. So, to receive the information you/they define an eventListener which listens for that event being dispatched. When the event is dispatched, the listener picks it up and then continues with the processing of the program.

              There are lots of sample material for events in the Adobe reference material so I suggest going through a few examples of what events are, and what they do.
              • 4. Re: EVENTS in flex
                Gregory Lafrance Level 6
                I would examine the FB3 help on events. Bascially, your UI just sits there "waiting" for events to be dispatched by other components in response to user interaction with the UI, or else dispatched by data availability, for example in an HTTPService or WebService.

                I haven't looked at the code, so I don't know how productCatalogueEvent is being used in the area of code you are examining, but evidently an event was fired probably because of user activity that accesses the product catalog, perhaps by filtering what will be displayed.

                Spend a couple of hours in the FB3 help system reading up on events and you will be much clearer on what is going on.
                • 5. Re: EVENTS in flex
                  otisme
                  A handy way as well to approach the documentation is to look at the events associated with the particular component in question e.g. button.

                  Do a search in help docs FB3 for 'button'. You want to find out what events are associated with button, click 'Events' in the menu section associated with your find results for 'button', Scroll down until you see a section called 'Method Detail', this is a list of all the methods associated with button events, e.g 'clickHandler() method

                  See this kind of info:

                  protected function clickHandler(event:MouseEvent):void

                  Default handler for the MouseEvent.CLICK event

                  Other info here gives other methods e.g mouseDownHandler() method.

                  so now you have enough info to use in your code eg

                  <mx:Script>
                  <![CDATA[
                  private function clickHandler(event:MouseEvent):void
                  {
                  myMessage.text='You clicked it';


                  }
                  <mx:Button label="Hi There" click="clickHandler()"/>
                  <mx:Label text="Label" id="myMessage"">

                  Of note is the fact that you get the info clickHandler(event:MouseEvent)
                  from searching 'button' in the help docs. Hope this helps get you started.

                  Colm
                  • 6. Re: EVENTS in flex
                    otisme Level 1
                    Hi,

                    Should have said also, for a look at more complex event handlers and event management in Flex Applications, you won't miss out by having a look on lynda.com at David Gassner's series of video tutorials on 'Flex 3 Essential Training' - also Beyond the Basics

                    cheers


                    Colm