Problem Extending the Dialog component from Flex

Question

I'm trying to extend the flex Dialog component () for usage in Xcelcius, I can package my component successfully and add it to the add-ons in Xcelsius. The problem is that if I try to drag and drop the component to the Xcelsius workspace, the component appears blank and halts the IDE a bit. Does anyone have an idea what I might be doing wrong?
my code is as follows:
package com.component.xcelsius.component
     import flash.text.TextFormatAlign;
     import mx.containers.TitleWindow;
     import mx.controls.Label;
     import mx.core.ScrollPolicy;
     [CxInspectableList ("title", "showTitle")]
     public class ErrorMessageHandler extends TitleWindow
          private var _titleChanged:Boolean = true;
          private var _valueChanged:Boolean = true;
          private var _titleText:String = "My Own";
          private var _showTitle:Boolean = true;
          private var _visible:Boolean = true;
          public function ErrorMessageHandler()
               super();
          [Inspectable(defaultValue="Title", type="String")]
          public override function get title():String
               return _titleText;
          public override function set title(value:String):void
               if (value == null)  value = "";
               if (_titleText != value)
                    _titleText = value;
                    _titleChanged = true;
                    invalidateProperties();
          override protected function createChildren():void
               super.createChildren();
               // Allow the user to make this component very small.
               this.minWidth = 200;
               this.minHeight= 25;
               // turn off the scroll bars
               this.horizontalScrollPolicy = ScrollPolicy.OFF;
               this.verticalScrollPolicy = ScrollPolicy.OFF;
          override protected function commitProperties():void
               super.commitProperties();
               if (this._titleChanged)
                    this.title = _titleText;
                    this.visible = true;
                    this.showCloseButton = true;
                    invalidateDisplayList();  // invalidate in case the titles require more or less room.
                    _titleChanged = false;
               if (this._valueChanged)
          // Override updateDisplayList() to update the component
        // based on the style setting.
          override protected function updateDisplayList(unscaledWidth:Number, unscaledHeight:Number):void
               super.updateDisplayList(unscaledWidth, unscaledHeight);

Answer 1

Hi,
First of all make sure you compile your Flex project with Flex SDK 2.0.1 Hotfix 3?
In the Add-on Packager carefully check your classname (the full class path + class name) because Xcelsius creates an instance of that class when you drag the add-on onto the canvas, so if it doesn't create anything usually it means your classname is wrong in the packager.
In your case:   
com.component.xcelsius.component.ErrorMessageHandler
If none of that works try extending from VBox as the top-level add-on class instead and see if that works (I have never tried with a TitleWindow).
Regards
Matt