Problem with standardization of the new Bead ComboBoxItemByField

[Raúl Núñez]

Hi:

I commited a PR (869) with a new Bead for ComboBox: ComboBoxItemByField.

Yishay said me that it could be very interesting to make some changes in
order to use the bead in a more generic way.

I've tried apply those changes but I haven't got it to work.

My problem is selectionChangedHandler never launches. I have checked with
another events as selectedItemChanged and selectedIndexChanged. Since the
handler is never launched, the selectedValue variable is not updated.


ComboBoxItemByField changes:

////////////////////////////////////////////////////////////////////////////////
//
//  Licensed to the Apache Software Foundation (ASF) under one or more
//  contributor license agreements.  See the NOTICE file distributed with
//  this work for additional information regarding copyright ownership.
//  The ASF licenses this file to You under the Apache License, Version 2.0
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////////////////////////////////////////////////////////////////////////////////
package org.apache.royale.jewel.beads.controls.combobox
{
  import org.apache.royale.core.IBead;
  import org.apache.royale.core.IStrand;
  import org.apache.royale.collections.CollectionUtils;
  import org.apache.royale.events.Event;
  import org.apache.royale.collections.ICollectionView;
  import org.apache.royale.core.ISelectionModel;

  /**
     *  The _modelItemByField class is a specialty bead that can be used with
     *  any _model control. This bead allows to select an item by field
     *
     *  @langversion 3.0
     *  @playerversion Flash 10.2
     *  @playerversion AIR 2.6
     *  @productversion Royale 0.9.4
     */

  public class ComboBoxItemByField implements IBead{

      protected var _model:ISelectionModel;
      protected var _strand:IStrand;


        /**
         *  constructor.
         *
         *  @langversion 3.0
         *  @playerversion Flash 10.2
         *  @playerversion AIR 2.6
         *  @productversion Royale 0.9.4
         */
      public function ComboBoxItemByField()
        {
        }

        /**
         *  @copy org.apache.royale.core.IBead#strand
         *
         *  @langversion 3.0
         *  @playerversion Flash 10.2
         *  @playerversion AIR 2.6
         *  @productversion Royale 0.9.7
         */
        public function set strand(value:IStrand):void
        {
            _strand = value;
            _model = _strand.getBeadByType(ISelectionModel) as
ISelectionModel;
            _model.addEventListener("selectionChanged"
, selectionChangedHandler);
            updateHost();
        }

        private var _valueField:String;
        /**
         *  The string that will be used for comparison field name
         *
         *  @langversion 3.0
         *  @playerversion Flash 10.2
         *  @playerversion AIR 2.6
         *  @productversion Royale 0.9.4
         */
        public function get valueField():String
        {
            return _valueField;
        }
        public function set valueField(value:String):void
        {
            _valueField = value;
            updateHost();
        }

        private var _selectedValue:*;

        /**
         *  Any kind of object to perform the comparison or select
         *  the item with this value in the field.
         *
         *  @langversion 3.0
         *  @playerversion Flash 10.2
         *  @playerversion AIR 2.6
         *  @productversion Royale 0.9.4
         */
        public function get selectedValue():*{
            return _selectedValue;
        }

        public function set selectedValue(value:*):void{
            _selectedValue = value;
            updateHost();
        }

        /**
         *  This bead allows update the selected item of the _model
through the entered field
         */
        protected function updateHost():void
        {
            if(_model && valueField != "" && selectedValue != null){
                var aux:* = CollectionUtils
.getItemByField(_model.dataProvider as ICollectionView
,valueField,selectedValue);
                if(aux == null){
                    _model.selectedItem = null;
                    _model.selectedIndex = -1;
                } else if (aux!==_model.selectedItem){
                    _model.selectedItem = aux;
                }
            }
        }

        /**
         *  Select the right item for the _model.
         *
         *  @param event
         */
        protected function selectionChangedHandler(event:Event):void{
            if(valueField != "" && _model){
                var selectedItem:Object = _model.selectedItem;
                if(selectedItem != null
 && selectedValue !== selectedItem[valueField])
                    selectedValue = selectedItem[valueField];
            }
        }

  }
}


Componente example:

 <j:ComboBox percentWidth="90" localId="comboCenter" labelField="displaytext"
dateprovider="{centers}">
                    <j:beads>
                        <j:ComboBoxItemByField valueField="code" localId=
"comboCenterItemByField" />
                    </j:beads>
                </j:ComboBox>

Thanks!!