R – Passing along information on a FileReference Complete event

actionscript-3apache-flexevents

I need to pass along a string with my FileReference, or provide that string as an argument when an event fires. To be clear, it really annoys me that AS3 doesn't allow you to pass parameters on events.

Right now, I've extended the FileReference class to include an additional variable. I'm trying to get this to compile, but it won't compile; I think I don't know how to import this class correctly. If you can tell me how to import this class correctly so that I no longer get Error: Type was not found or was not a compile-time constant at compile time that would be great.

This is the extended FileReference class:

import flash.net.FileReference;

public class SxmFR extends FileReference {

  public var housenum:String = "";

  public function SxmFR(str:String) {
      housenum = str;
      super();
  }
}

I've tried that in a .mxml and a .as in the same folder. Neither is automatically imported.

I've also tried to extend the Event class, but I couldn't figure out how to make the event dispatch, since I need to respond to the Event.COMPLETE event. If you can tell me how to make it dispatch on this, it also might work.

Please help me get this figured out, and much love and thanks to all involved. : )

Best Answer

If you add your event listener as a closure you have access to the variables in the current function:

function myFunction(): void {
    var aParam: String = "This is a parameter";

    dispatcher.addEventListener("eventName", function (e: Event): void {
        // you can access aParam here
        trace(aParam);
    });
}

The aParam inside the function will have the same value as it had when addEventListener was called.

Related Solutions

Javascript – Event binding on dynamically created elements

As of jQuery 1.7 you should use jQuery.fn.on with the selector parameter filled:

$(staticAncestors).on(eventName, dynamicChild, function() {});

Explanation:

This is called event delegation and works as followed. The event is attached to a static parent (staticAncestors) of the element that should be handled. This jQuery handler is triggered every time the event triggers on this element or one of the descendant elements. The handler then checks if the element that triggered the event matches your selector (dynamicChild). When there is a match then your custom handler function is executed.

Prior to this, the recommended approach was to use live():

$(selector).live( eventName, function(){} );

However, live() was deprecated in 1.7 in favour of on(), and completely removed in 1.9. The live() signature:

$(selector).live( eventName, function(){} );

... can be replaced with the following on() signature:

$(document).on( eventName, selector, function(){} );

For example, if your page was dynamically creating elements with the class name dosomething you would bind the event to a parent which already exists (this is the nub of the problem here, you need something that exists to bind to, don't bind to the dynamic content), this can be (and the easiest option) is document. Though bear in mind document may not be the most efficient option.

$(document).on('mouseover mouseout', '.dosomething', function(){
    // what you want to happen when mouseover and mouseout 
    // occurs on elements that match '.dosomething'
});

Any parent that exists at the time the event is bound is fine. For example

$('.buttons').on('click', 'button', function(){
    // do something here
});

would apply to

<div class="buttons">
    <!-- <button>s that are generated dynamically and added here -->
</div>

Javascript – jQuery Event Keypress: Which key was pressed

Actually this is better:

 var code = e.keyCode || e.which;
 if(code == 13) { //Enter keycode
   //Do something
 }

Best Answer

Related Solutions

Javascript – Event binding on dynamically created elements

Javascript – jQuery Event Keypress: Which key was pressed

Related Topic