今天學習Cairngorm,找了份教程,寫了個Demo,以記錄並分享學習過程。
Cairngorm的各個部分:
1.ModelLocator:在一個地方存儲程序中所有的值對象(ValueObjects,數據)並共享變量。它與HTTP Session對象相類似,不過它存儲在Flex客戶端,而不是存儲在一箇中間層程序服務器的服務器端。
2.View(視圖):一個或多個Flex組件(Button,panel,combo Box,Tile等等)綁定到一起形成的一個特定的個體,使用ModelLocator中的數據並且針對用戶的交互動作(如點擊,鼠標滑過,拖拽等)產生自定義的CairngormEvents。
3.FrontController(前端控制器):接受CairngormEvents並且將它們映射到CairngormCommands。
4.Command(命令):處理業務邏輯,調用CairngormDelegates或其他的Commands,以及更新ModelLocator中存儲的值對象和變量。
5.Delegate(委託):由一個Command創建,它將遠程過程實例化並且將結果返回給Command。
6.Service(服務):定義鏈接到遠程數據庫的遠程過程調用(HTTP,Web Services等)。
Cairngorm的工作流程大體是這樣:
客戶端界面由View組成的。View使用Flex的binding(綁定)來顯示ModelLocator中包含的數據。View根據諸如鼠標點擊,按鈕按下以及拖拽之類的用戶動作產生Event。這些Event被FrontController“廣播”並“監聽”,FrontController會將Event映射到Command。Command包括業務邏輯,創建所需的Delegate,處理Delegate的響應,以及更新存儲在ModelLocator中的數據。由於View是綁定到ModelLocator中的數據上的,所以當ModelLocator中的數據改變的時候View也會自動更新。Delegate調用Service並且將結果提交給Command,這一步是可選的,但是推薦這麼做。Service調用遠程數據然後將結果提交給Delegate。
Delegate的最簡單的形式就是一箇中間人的角色。如果一個Command需要調用webservice來獲得一些數據,它將創建一個Delegate來完成這個調用。一個Command創建一個Delegate,Delegate調用一個指定的dataService,Service返回結果給Delegate,Delegate返回結果給Command。
Delegate並不是100%必需的,但是當涉及測試&程序環境的時候它們很有幫助。相對於在Command代碼中使用查找替換改變所有的引用來測試,將一個Delegate重映射到一個測試Service更爲簡單。
下面說我的Demo:完成用戶登錄在後臺進行驗證合法性,並反饋給前臺。
工具及環境介紹,詳見該文章:Flex + blazeds + J2EE 數據交互入門實例教程(圖)
版本說明:
Flex:Flex 4;
ActionScript:ActionScript 3;
Java JDK:jdk1.6.0_20
Cairngorm,我用的是版本2.2,好像Cairngorm 3已經發布了,但是官網沒提供下載。下載cairngorm2_2_1-bin.zip,我們要用的已經打包好的資源文件Cairngorm.swc,將其拷貝到Flex工程的libs目錄下面即可。
1.後臺Java服務端項目CairngormDemo工程組成:
相應代碼:
UserVO.java
package net.dreamhui.java;
public class UserVO {
public String userName;
public String passWord;
// 和ActionScript對應得構造方法
public UserVO() {
}
// getters & setters
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getPassWord() {
return passWord;
}
public void setPassWord(String passWord) {
this.passWord = passWord;
}
}
LoginUser.java
package net.dreamhui.java;
public class LoginUser {
public UserVO currentUser;
private String uName;
private String pWord;
// Flex端要調用的服務
public UserVO login(UserVO par_user) {
// UserVO par_user2 = UserVO(par_user);
uName = par_user.userName;
pWord = par_user.passWord;
if (uName.equalsIgnoreCase("wwh") && pWord.equalsIgnoreCase("wwh")) {
return par_user;
// return "歡迎用戶:"+uName;
} else {
return null;
// return "用戶名或密碼錯誤,請重新輸入";
}
}
}
2.前臺Flex工程CairngormDemo工程組成:
按照 ValueObjects模型(UserVO.as)——>模型定位(UserModelLocator.as)——>視圖(loginView.mxml及主應用視圖CairngormDemo.mxml)——>事件(LoginEvent.as)——>前端控制器(LoginController.as)——>Command(LoginCommand.as)——>委派代理(LoginDelegate.as)——>服務定位(LoginServiceLocator.mxml)依次的相應代碼如下(因爲文件中註釋較多,不多寫註解):
UserVO.as
package net.dreamhui.vo
{
/**
* 我看的教程裏面講綁定ValueObject到遠程Java類的方法是這樣的,
* public static var registered:Boolean = this.registerClass();
* 可能又是版本問題,在我這兒是通不過的,我到網上找到了如下的解決方法:
* [RemoteClass(alias="net.dreamhui.java.UserVO")],
* 估計是我看的教程版本太低了,呵呵
* */
import com.adobe.cairngorm.vo.ValueObject;
[Bindable]
[RemoteClass(alias="net.dreamhui.java.UserVO")]
public class UserVO implements ValueObject
{
private var _userName:String;
private var _passWord:String;
/**
* 爲了實現遠程Class之間的綁定,構造方法必須形式上完全一致,
* 包括參數的個數和類型,否則會出現異常。
* */
public function UserVO()
{
}
//getters & setters
public function get userName():String
{
return _userName;
}
public function set userName(value:String):void
{
_userName = value;
}
public function get passWord():String
{
return _passWord;
}
public function set passWord(value:String):void
{
_passWord = value;
}
}
}
UserModelLocator.as
package net.dreamhui.model
{
import com.adobe.cairngorm.CairngormError;
import com.adobe.cairngorm.CairngormMessageCodes;
import com.adobe.cairngorm.model.ModelLocator;
import flash.events.Event;
import net.dreamhui.vo.UserVO;
//綁定全局View數據
[Bindable]
public class UserModelLocator implements ModelLocator
{
private var _currentUser:UserVO;
public static const LOGIN_YES:String = "loginYes";
private static var instance:UserModelLocator;
//單例模式
public function UserModelLocator()
{
if(instance == !null)
{
throw new CairngormError(CairngormMessageCodes.SINGLETON_EXCEPTION,"UserModelLocator");
}
instance = this;
}
public static function getInstance():UserModelLocator
{
if(instance == null)
{
instance = new UserModelLocator();
}
return instance;
}
public function get currentUser():UserVO
{
return _currentUser;
}
/**
* 此賦值操作綁定loginYes事件,當輸入數據合法時候,將改變當前的登錄狀態
* **/
[Bindable("loginYes")]
public function set currentUser(value:UserVO):void
{
_currentUser = value;
dispatchEvent(new Event(UserModelLocator.LOGIN_YES));
}
}
}
loginView.mxml<?xml version="1.0" encoding="utf-8"?>
<s:Panel xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
title="請登陸" currentState="initState"
creationComplete="lvcreationComplete(event)">
<!--~~~~~~~~~~~~~~~~~~~~~~Script~~~~~~~~~~~~~~~~~~~~~~-->
<fx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.events.FlexEvent;
import mx.rpc.events.FaultEvent;
import mx.rpc.events.ResultEvent;
import mx.validators.Validator;
import mx.events.ValidationResultEvent;
import mx.core.UIComponent;
import net.dreamhui.control.LoginEvent;
import net.dreamhui.model.UserModelLocator;
import net.dreamhui.vo.UserVO;
/***************************************************/
private var validObjs:Array;
/***************************************************/
protected function lvcreationComplete(event:FlexEvent):void
{
validObjs = [unSV,pwSV];
}
protected function submit(event:MouseEvent):void
{
var validatorResults:Array;
validatorResults = Validator.validateAll(validObjs);
if(validatorResults.length == 0)
{
var user:UserVO = new UserVO();
user.userName = uName.text;
user.passWord = pWord.text;
var lgEvent:LoginEvent = new LoginEvent(LoginEvent.LOGIN_USER);
lgEvent.data = user;
lgEvent.dispatch();
//派發事件
/***LoginEvent繼承自com.adobe.cairngorm.control.CairngormEvent,
* 用父類的方法dispatch派發事件;
* 其實CairngormEvent繼承自flash.events.Event
* dispatch是CairngormEventDispatcher類封裝IEventDispatcher
* 的dispatchEvent()方法
* **/
}
else
{
//定義校驗出錯事件
var vEvent:ValidationResultEvent;
//取出第一個出錯事件
vEvent = validatorResults[0] as ValidationResultEvent;
//將光標定位到第一個出錯的組件上
(vEvent.target.source as UIComponent).setFocus();
}
}
]]>
</fx:Script>
<!--~~~~~~~~~~~~~~~~~~~~~~states~~~~~~~~~~~~~~~~~~~~~~-->
<s:states>
<s:State name="initState"/>
<s:State name="loginState"/>
</s:states>
<!--~~~~~~~~~~~~~~~~~~~~~~Declarations~~~~~~~~~~~~~~~~~~~~~~-->
<fx:Declarations>
<!--定義用戶名和密碼的輸入校驗類-->
<mx:StringValidator id="unSV"
source="{uName}"
property="text"
required="true"
maxLength="10"
tooLongError="用戶名最長爲10位"
requiredFieldError="請填寫用戶名" />
<mx:StringValidator id="pwSV"
source="{pWord}"
property="text"
required="true"
maxLength="10"
tooLongError="密碼最長爲10位"
requiredFieldError="請填寫密碼" />
</fx:Declarations>
<!--~~~~~~~~~~~~~~~~~~~~~~UI Components~~~~~~~~~~~~~~~~~~~~~~-->
<mx:Form includeIn="initState">
<mx:FormItem label="用戶名" >
<s:TextInput id="uName" />
</mx:FormItem>
<mx:FormItem label="密 碼" >
<s:TextInput id="pWord" displayAsPassword="true" />
</mx:FormItem>
<mx:FormItem>
<s:Button id="submitBtn" click="submit(event)" label="登陸" right="0" />
</mx:FormItem>
</mx:Form>
<s:HGroup includeIn="loginState" top="20" left="10" >
<s:Label text="歡迎尊貴的用戶:"/>
<s:Label id="cuName" text="{UserModelLocator.getInstance().currentUser.userName}" />
</s:HGroup>
</s:Panel>
CairngormDemo.mxml<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
xmlns:business="net.dreamhui.business.*"
xmlns:control="net.dreamhui.control.*"
xmlns:view="net.dreamhui.view.*"
creationComplete="creationComplete()">
<!--~~~~~~~~~~~~~~~~~~~~~~Script~~~~~~~~~~~~~~~~~~~~~~-->
<fx:Script>
<![CDATA[
import mx.controls.Alert;
import mx.events.FlexEvent;
import net.dreamhui.model.UserModelLocator;
/***************************************************/
protected function creationComplete():void
{
UserModelLocator.getInstance().addEventListener(UserModelLocator.LOGIN_YES,switchState);
}
protected function switchState(event:Event):void
{
lgView.currentState = "loginState";
}
]]>
</fx:Script>
<!--~~~~~~~~~~~~~~~~~~~~~~Declarations~~~~~~~~~~~~~~~~~~~~~~-->
<fx:Declarations>
<!--初始化服務,裏面含有Command註冊 和 遠程過程調用的信息-->
<business:LoginServiceLocator id="lgService" />
<control:LoginController id="loginContr" />
<!--<commands:LoginCommand id="lCommand" />-->
<!--<model:UserModelLocator id="uLocator" />-->
</fx:Declarations>
<!--~~~~~~~~~~~~~~~~~~~~~~UI Components~~~~~~~~~~~~~~~~~~~~~~-->
<view:loginView id="lgView" top="10" horizontalCenter="0" width="30%"
height="30%" fontSize="20"/>
</s:Application>
LoginEvent.aspackage net.dreamhui.control
{
import com.adobe.cairngorm.control.CairngormEvent;
import net.dreamhui.vo.UserVO;
public class LoginEvent extends CairngormEvent
{
//定義事件類型常量
public static const LOGIN_USER:String = "loginUser";
public function LoginEvent(type:String, bubbles:Boolean=false, cancelable:Boolean=false)
{
super(type, bubbles, cancelable);
}
}
}
LoginController.aspackage net.dreamhui.control
{
import com.adobe.cairngorm.control.FrontController;
import net.dreamhui.commands.LoginCommand;
public class LoginController extends FrontController
{
public function LoginController()
{
initCommands();
}
/**註冊Command*/
private function initCommands():void
{
addCommand(LoginEvent.LOGIN_USER,LoginCommand);
}
}
}
LoginCommand.aspackage net.dreamhui.commands
{
import com.adobe.cairngorm.commands.ICommand;
import com.adobe.cairngorm.control.CairngormEvent;
import mx.controls.Alert;
import mx.rpc.IResponder;
import net.dreamhui.business.LoginDelegate;
import net.dreamhui.control.LoginEvent;
import net.dreamhui.model.UserModelLocator;
import net.dreamhui.vo.UserVO;
public class LoginCommand implements ICommand,IResponder
{
public function LoginCommand()
{
}
public function execute(event:CairngormEvent):void
{
//Alert.show("execute");
var lgEvent:LoginEvent = LoginEvent(event);
var user:UserVO = lgEvent.data;
var delegate:LoginDelegate = new LoginDelegate(this);
delegate.login(user);
}
/**
* Command實現IResponder接口的兩個方法result和fault;
* 我看了兩份教程,前者是這樣的:
* 1、Command實現com.adobe.cairngorm.business.Responder接口的onResult和onFault兩個方法;
* 2、Command實現mx.rpc.IResponder接口的兩個方法result和fault;
* 因爲我在LoginDelegate沒能實現將內部變量設置爲com.adobe.cairngorm.business.Responder,
* 所以,我採用了第二種方案,通過。
* */
public function result(event:Object):void
{
var cuUser:UserVO = event.result as UserVO;
if(cuUser)
{
UserModelLocator.getInstance().currentUser = cuUser;
//此賦值操作綁定loginYes事件,當輸入數據合法時候,將改變當前的登錄狀態
//Alert.show(cuUser.userName);
}
else
{
Alert.show("用戶名或密碼錯誤,請重新填寫");
}
}
public function fault(event:Object):void
{
trace("服務調用錯誤"+event.toString());
}
}
}
LoginDelegate.aspackage net.dreamhui.business
{
import com.adobe.cairngorm.business.ServiceLocator;
import mx.rpc.IResponder;
import net.dreamhui.vo.UserVO;
public class LoginDelegate
{
public var responder:IResponder;
public var service:Object;
public function LoginDelegate(responder:IResponder)
{
this.service = ServiceLocator.getInstance().getRemoteObject("loginService");
//this.service = ServiceLocator.getInstance().getService("loginService");
//我看的教程裏採用下面的做法,程序運行沒有問題,只是會有warning
this.responder = responder;
}
public function login(user:UserVO):void
{
var call:Object = service.login(user);
//call.resultHandler = Delegate.create(responder, responder.onResult);
//call.faultHandler = Delegate.create(responder, responder.onFault);
//註釋掉的部分是教程裏的寫法,可能是版本的問題,在我這兒是不對的
call.addResponder(responder);
}
}
}
LoginServiceLocator.mxml<?xml version="1.0" encoding="utf-8"?>
<rds:ServiceLocator xmlns:rds="com.adobe.cairngorm.business.*"
xmlns:mx="http://www.adobe.com/2006/mxml">
<!--
<cairngorm:ServiceLocator
xmlns:fx="http://ns.adobe.com/mxml/2009"
xmlns:s="library://ns.adobe.com/flex/spark"
xmlns:mx="library://ns.adobe.com/flex/mx"
xmlns:cairngorm="http://www.adobe.com/2006/cairngorm">
~~~~~~~~~~~~~~~~~~~~~~Declarations~~~~~~~~~~~~~~~~~~~~~~
<fx:Declarations>
<s:RemoteObject id="loginService"
destination="loginUser"
showBusyCursor="true"
/>
</fx:Declarations>
</cairngorm:ServiceLocator>
-->
<mx:RemoteObject id="loginService" destination="loginUser" showBusyCursor="true"
endpoint="/FlexWeb/messagebroker/amf"/>
</rds:ServiceLocator>
最後工程運行結果:
注:
1)在原文基礎上略有修改,原文地址:http://blog.dreamhui.net/archives/64
2)Q:LoginServiceLocator.mxml報錯。 xmlns:cairngorm="http://www.adobe.com/2006/cairngorm"> 這一行 Could not resolve <cairngorm:ServiceLocator> to a component implementation.
A:這個問題確定已將libs中的Cairngorm.swc添加到了構建路徑庫中後,LoginServiceLocator.mxml就用上文中的即可;反之,原代碼是註釋中的內容。
3)上文中圖片是本人自行添上的,原文中的圖顯示不了,應該與原文有所不同,還請見諒……4)Cairngorm相關:
基於 Cairngorm MVC 框架的 Flex 程序設計與開發:http://www.ibm.com/developerworks/cn/web/1008_zhaifeng_cairngorm/
Flex Cairngorm詳解:http://www.cnblogs.com/zhainanJohnny/archive/2010/11/28/1890301.html