BlazeDS Flex端常用方法总结 及 ResultEvent分析

1 .基本使用:

	private var op:AbstractOperation;
	public function loadEmployees():void {
		op = AppContext.getRemoteObject().getOperation("loadEmployees");	//获得Operation
		 op.arguments = [id];	//设定参数
		 var at:AsyncToken = op.send();	//Send
		 at.addResponder(this);	//为本实例增加responder

      }

//---------------------实现 IResponder-------------------------------
	public function result(responderResult:Object):void {
		var resultEvent:ResultEvent = responderResult as ResultEvent;
		var ac:ArrayCollection = resultEvent.result as ArrayCollection;//result为服务器返回的数据
		log.debug("已读取到 " + this + "的职员列表, 职员数目为: " + ac.length);
	}

	public function fault(data:Object):void {
		throw new Error("远程操作失败");
	}

2. 另外可通过外置Responder实例来响应结果, 同时在实例中dispatch Event, 可实现在当前类中响应服务器端返回数据.

	//Listener - onButtonDelClicked
	private function onButtonDelClicked(e:MouseEvent):void {
		var op:AbstractOperation = AppContext.getRemoteObject().getOperation("delEmp");
		log.info("Deleteing...");
			 op.arguments = [datagridEmpList.selectedItem as Employee];
			 var at:AsyncToken = op.send();
			 var rs:OperationResponder = new OperationResponder();//增加Responder实例
			 rs.addEventListener(OperationResultEvent.OPERATION_COMPLETE, onOperationSuccess);//监听由Responder派发的Custom Event
			 at.addResponder(rs);//为AsyncToken增加Responder
	}

//-----------------------on RemoteOperationSuccess - SaveNew - UPdate - Delete - load Department- 监听多个操作的Event-----------------
	private function onOperationSuccess(e:OperationResultEvent):void {
		var resultEvent:ResultEvent = e.resultData as ResultEvent;
		var resultEventATMessage:RemotingMessage = resultEvent.token.message as RemotingMessage;
		var operationName:String = resultEventATMessage.operation;
		if(operationName == "saveEmpToDB") {//新建保存
			//....
		}else if(operationName == "updateEmp"){	//更新
			//....
			}
		}else if(operationName == "delEmp") {//删除
			var deletedEmp:Employee = resultEventATMessage.body[0];
			log.info("已成功删除职员: " + deletedEmp.name);
		}else if(operationName == "loadDepartments") {	//加载部门信息
		//...
		}
	}

OperationResponder类:

package com.insprise.dept.view
{
/**
 * Select Departments Responder
 */
 [Event(name = "OperationComplete", type="com.insprise.dept.event.OperationResultEvent")]
public class OperationResponder  extends EventDispatcher implements IResponder
{
	public function OperationResponder() {
		super();
	}

	public function result(data:Object):void {
//		var resultEvent:ResultEvent = data as ResultEvent;
//		var ac:ArrayCollection = resultEvent.result as ArrayCollection;
		dispatchEvent(new OperationResultEvent(data));
	}

	public function fault(info:Object):void {
		throw new Error("服务器出错 - 调用服务器端方法失败" +  ErrorMessage);
	}
}//end of class
}//end of package

OperationResultEvent类:

package com.insprise.dept.event
{
/**
 * when Operation Success, and it's responder can dispatch this event
 */
public class OperationResultEvent extends Event
{
	public static const OPERATION_COMPLETE:String = "OperationComplete";
	private var _resultData:Object;

	/**
	 * Constructor
	 */
	public function OperationResultEvent(resultData_:Object) {
		super(OPERATION_COMPLETE, false, false);
		_resultData = resultData_;
	}

	/**
	 * Getter
	 */
	 public function get resultData():Object {
	 	return _resultData;
	 }

	/**
	 * Override - MUST
	 */
	 override public function clone():Event {
	 	return new OperationResultEvent(_resultData);
	 }

	/**
	 * OPTIONAL
	 */
	 override public function toString():String {
	 	return formatToString(OPERATION_COMPLETE, "_resultData");
	 }
}//end of class
}//end of package

3: ResultEvent常用操作:

ResultEvent由AsyncToken的applyResult方法派发, 将该Event传递至Responder的result方法中.

ResultEvent的属性:

    /**
     * Creates a new ResultEvent.
     * @param type The event type; indicates the action that triggered the event.
     * @param bubbles Specifies whether the event can bubble up the display list hierarchy.
     * @param cancelable Specifies whether the behavior associated with the event can be prevented.
     * @param result Object that holds the actual result of the call.
     * @param token Token that represents the call to the method. Used in the asynchronous completion token pattern.
     * @param message Source Message of the result.
     */
    public function ResultEvent(type:String, bubbles:Boolean = false, cancelable:Boolean = true,
                                result:Object = null, token:AsyncToken = null, message:IMessage = null)
    {
        super(type, bubbles, cancelable, token, message);

        if (message != null && message.headers != null)
            _statusCode = message.headers[AbstractMessage.STATUS_CODE_HEADER] as int;

        _result = result;
    }

resultEvent.result存放有当前op返回值, 可通过ObjectUtils.toString(resultEvent.result)来查看其类型及信息

其中token中存放有如下具体信息:

Message中的内容:

body中存放有当前Operation的很多参数, 可使用如下方法调用Message:

var resultEventATMessage:RemotingMessage = resultEvent.token.message as RemotingMessage;

然后可通过resultEventATMessage.operation / desination/body[*]等来调用op/destination名字及op的参数.

在Operation中定义了message的内容:

以下代码来自mx.rpc.remoting.Operaiton

    override public function send(... args:Array):AsyncToken
    {
        if (!args || (args.length == 0 && this.arguments))
        {
            if (this.arguments is Array)
            {
                args = this.arguments as Array;
            }
            else
            {
                args = [];
                for (var i:int = 0; i < argumentNames.length; ++i)
                {
                    args[i] = this.arguments[argumentNames[i]];
                }
            }
        }

        var message:RemotingMessage = new RemotingMessage();
        message.operation = name;
        message.body = args;
        message.source = RemoteObject(service).source;

        return invoke(message);
    }

}