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这类似于这里提出的问题。我正在调度自定义事件“ShopEvent”，但出现错误“类型强制失败：无法将 flash.events::Event@81ecb79 转换为 com.events.ShopEvent”

注意：父自定义组件（第三个代码片段）抛出错误，我在那里添加了更多详细信息

这是我的自定义事件。查看第一个常量，我将事件名称复制粘贴到自定义组件中。

package com.events
{
    import flash.events.Event;

    public class ShopEvent extends Event
    {

        public static var MENU_SELECTED:String = "menuSelected";
        public static var SUBMENU_SELECTED:String = "submenuSelected";
        public static var ITEM_SELECTED:String = "itemSelected";
        public static var NAV_NEXT:String = "navNext";
        public static var NAV_PREVIOUS:String = "navPrevious";
        public static var NAV_LAST:String = "navLast";
        public static var NAV_FIRST:String = "navFirst";
        public static var CLOSE:String = "close";

        public var menuIdx:int;
        //public var menuType:String;
        public var menuId:int;
        public var menuName:String;
        public var itemId:int;
        public function ShopEvent(type:String, bubbles:Boolean=false, cancelable:Boolean=false)
        {
            super(type, bubbles, cancelable);
        }
    }
}

自定义组件。检查元数据标签。事件注册正确

<?xml version="1.0" encoding="utf-8"?>
<s:Group xmlns:fx="http://ns.adobe.com/mxml/2009" 
         xmlns:s="library://ns.adobe.com/flex/spark" 
         xmlns:mx="library://ns.adobe.com/flex/mx" width="72" height="82"
         mouseChildren="false"
         creationComplete="init()"
         click="onClick()"
         buttonMode="true">
    <s:layout>
        <s:VerticalLayout horizontalAlign="center"/>
    </s:layout>
    <fx:Script>
        <![CDATA[
            import com.events.ShopEvent;

            import mx.controls.Image;
            public var menuId:int;

            [Bindable]
            public var menuText:String;
            [Bindable]
            public var bmp:Bitmap;

            private function init():void{
                //img.addChild(bmp);
            }
            private function onClick():void{
                var e:ShopEvent = new ShopEvent(ShopEvent.MENU_SELECTED);
                e.menuId = menuId;
                e.menuName = menuText;
                dispatchEvent(e);
            }

        ]]>

    </fx:Script>
    <fx:Metadata>
        [Event(name="menuSelected", type="com.events.ShopEvent")]
    </fx:Metadata>
    <fx:Declarations>
        <!-- Place non-visual elements (e.g., services, value objects) here -->
    </fx:Declarations>
    <s:Label text="{menuText}" fontWeight="bold" fontSize="12" width="44"/>
    <mx:Image id = "img" width="57" height="47" source="{bmp}"/>

</s:Group>

父自定义组件。这是上述自定义组件的父组件。它侦听 menuSelected 事件并将事件简单地路由到侦听器。检查肉类数据标签。事件注册已正确完成。

However, the error is coming at

           menus[i].addEventListener( ShopEvent.MENU_SELECTED,function(e:ShopEvent):void{dispatchEvent(e);});

with my knowledge, I dont see any problem in the code. Is there anything wrong in it?

Update

Surprisingly, if I create a "new" instance of shopwevent will solve the problem, but sadly, I need to close all the properties of the event object. I hope this is not a limitation of flex. 

                menus[i].addEventListener( ShopEvent.MENU_SELECTED,function(e:ShopEvent):void{dispatchEvent(new ShopEvent(ShopEvent.MENU_SELECTED));});

Complete code

<?xml version="1.0" encoding="utf-8"?>
<s:Group xmlns:fx="http://ns.adobe.com/mxml/2009" 
         xmlns:s="library://ns.adobe.com/flex/spark" 
         xmlns:mx="library://ns.adobe.com/flex/mx"
         width="720" height="605"
         creationComplete="init()" xmlns:shop="UI.shop.*" xmlns:hasu="UI.shop.hasu.*"
         >
    <fx:Declarations>
        <!-- Place non-visual elements (e.g., services, value objects) here -->
    </fx:Declarations>
    <fx:Metadata>
        [Event(name="navNext", type="com.events.ShopEvent")]
        [Event(name="navPrevious", type="com.events.ShopEvent")]
        [Event(name="menuSelected", type="com.events.ShopEvent")]
        [Event(name="submenuSelected", type="com.events.ShopEvent")]
        [Event(name="itemSelected", type="com.events.ShopEvent")]
        [Event(name="close", type="com.events.ShopEvent")]
    </fx:Metadata>

    <fx:Script>
        <![CDATA[
            import com.events.ShopEvent;

            private const MAX_SLOTS:int = 6;

            public var menus:Vector.<ShopMenuItemView>;
            public var itemSlots:Vector.<ShopItemSlotView> = new Vector.<ShopItemSlotView>(MAX_SLOTS);

            private function init():void{
                trace("BEGIN:UI.shop.hasu.ShopView.init");
                initSlots();
            }

            private function initSlots():void{

                for (var i:int = 0;i<itemSlots.length;i++){
                     var slot:ShopItemSlotView = new ShopItemSlotView();
                    itemSlots[i] = slot; 
                    itemSlotsContainer.addElement(slot);
                }
            }

            public function initMenus():void{
                trace("BEGIN:UI.shop.hasu.ShopView.initMenus");
                for (var i:int = 0;i < menus.length;i++){
                    menuContainer.addElement(menus[i]);
                    menus[i].addEventListener(ShopEvent.MENU_SELECTED,function(e:ShopEvent):void{dispatchEvent(e);});
                    //menus[i].addEventListener( ShopEvent.MENU_SELECTED,function(e:ShopEvent):void{dispatchEvent(new ShopEvent(ShopEvent.MENU_SELECTED));});
                }
            }



        ]]>
    </fx:Script>

    <s:layout>
        <s:VerticalLayout />
    </s:layout>
    <s:VGroup name="top">
        <hasu:ShopPlayerAttributesView id="attribsComp"/>
        <s:Group id="menuContainer" name="menus">
            <s:layout>
                <s:HorizontalLayout />
            </s:layout>
        </s:Group>
    </s:VGroup>
    <s:Group>
        <s:layout>
            <s:HorizontalLayout />
        </s:layout>
        <s:Button label="&lt;" />
        <s:Group id = "itemSlotsContainer" name="items">
            <s:layout>
                <s:TileLayout requestedColumnCount="3" requestedRowCount="3"/>
            </s:layout>
        </s:Group>
        <s:Button label="&gt;" />
    </s:Group>
</s:Group>
4

4 回答 4

2

You must overwrite clone() method for custom event classes. Events could be cloned several times during propagation.

于 2012-02-16T08:24:00.590 回答
1

Jack's answer is correct. It is given in the flex documentation.

You are required to override the Event.clone() method in your subclass. The clone() method returns a cloned copy of the event object by setting the type property and any new properties in the clone. Typically, you define the clone() method to return an event instance created with the new operator.

For full details read Working with events under creating subclass from the event section

A good place to understand the custom events for new flex/as3 developers to read Dispatching the custom events

Note: the links are pointing to Flex 4.6 documentation but the custom events part is not version dependent (only mxml part may different for flex 3 and prior versions)

于 2012-03-02T04:40:32.790 回答
0

you must return new Constructor of the event class like:

return new ShopEvent(type,...); //in the clone() method;

The clone() method returns a cloned copy of the event object by setting the type property and any new properties in the clone. Typically, you define the clone() method to return an event instance created with the new operator.

于 2013-09-23T07:25:50.513 回答
-1

The event you are dispatching is from type flash.events.Event and the event that your listener is expecting for is from type: com.events.ShopEvent.

This is simply what the error message means.

于 2012-02-16T07:53:46.043 回答