Flex PureMVC 学习

本文来自：http://www.cnblogs.com/victorl/archive/2009/03/16/1413079.html

最近迷上Flex,研究了以下pureMVC,就我的学习过程写出来,给一些和我一样的迷途羔羊一点经验吧.我的不是教程,只是自己的学习过程.
首先,我会用一个Demo来说明我的学习过程.
分析:
1.选择自己需要进入的网站类型;
2.如果选择Flex,哪么就需要登陆.
以上是我现在Demo的雏形.
注:pureMVC我就不讲了.不懂的可以去看相关的资料.现在有中文版的资料.
第一步:建立好工程,加载进pureMVC的框架,建立好文件结构.
第一步:
首先是注册相关的通知,为了方便管理,我将所有的通知均放在一个as文件中,命名为AppConstance.as
代码如下:






1

package myApp

2

{

3

public class AppConstance

4

{

5

public function AppConstance()

6

{

7

}

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//注册通知;

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public static const START:String = "start";

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public static const TO_CHOOSE:String = "to_choose";

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public static const CHOOSE:String = "choose";

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public static const TO_LOGIN:String = "to_login";

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public static const LOGIN:String = "login";

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public static const LOGIN_SUCCESS:String = "login_success";

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public static const LOGIN_FAILURE:String = "login_failure"

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public static const TO_WELCOME:String = "to_welcome";

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public static const WELCOME:String = "welcome";

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}

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}



这里我注册了所有的通知,从程序开始一直到欢迎界面.
第二步:
在PureMVC中Facade只有一个,而且永远不会被实例化,本程序中Facade命名为:ApplicationFacade.as
代码如下






package myApp

{

import org.puremvc.as3.interfaces.IFacade;

import org.puremvc.as3.patterns.facade.Facade;

import myApp.AppConstance;

import myApp.Controller.startCommand;

public class ApplicationFacade extends Facade implements IFacade

{

public function ApplicationFacade()

{

super();

}

public static function getInstance():ApplicationFacade{

if(instance == null){

instance = new ApplicationFacade();

}

return instance as ApplicationFacade;

}

override protected function initializeController():void{

super.initializeController();

registerCommand(AppConstance.START,startCommand);

}

public function start(app:myApp):void{

sendNotification(AppConstance.START,app,"myweb");

}

}

}



解释下:


Code
这句是获得ApplicationFacade单列工厂,如果不存在则新创建一个,然后返回一个ApplicationFacade.



override protected function initializeController():void{

super.initializeController();

registerCommand(AppConstance.START,startCommand);

}
初始化Controller,并注册了START这个通知与startCommand的映射,注意,通知必须有相关的Command,Mediator对应.
然后创建开始函数:



public function start(app:myApp):void{

sendNotification(AppConstance.START,app,"myweb");

}
这里我传了一个参数:app:myApp,意思是传的参数app是myApp类型,myApp指主文件myApp.mxml.
到此ApplicationFacade创建完成,实现了开始函数:start(),单列工厂:getInstance(),还有初始化controller:initializeController();

第三步:
myApp.mxml
myApp属于一个空的Application,在程序开始运行时就需要去执行start();
见代码:






<?xml version="1.0" encoding="utf-8"?>

<mx:Application xmlns:mx="http://www.adobe.com/2006/mxml" layout="absolute" creationComplete="intApp()">

<mx:Script>

<![CDATA[

import myApp.ApplicationFacade;

public function intApp():void{

var facade:ApplicationFacade = ApplicationFacade.getInstance();

facade.start(this);

}

]]>

</mx:Script>

</mx:Application>




导入ApplicationFacade类. 声明一个函数为intApp()并在页面加载完成后执行:craationComplete = "intApp()";
声明了一个变量facade,类型是ApplicationFacade,并执行start(),这样程序就启动了..

第四步:
startCommand:
在ApplicationFacade中,我声明了AppConstance.START,这个通知与startCommand的映射,即,在程序开始执行时,就需要去执行startCommand
代码:






package myApp.Controller

{

import myApp.AppConstance;

import myApp.Model.userProxy;

import myApp.View.chooseMediator;

import myApp.View.loginMediator;

import org.puremvc.as3.interfaces.ICommand;

import org.puremvc.as3.interfaces.INotification;

import org.puremvc.as3.patterns.command.SimpleCommand;

public class startCommand extends SimpleCommand implements ICommand

{

public function startCommand()

{

super();

}

override public function execute(notification:INotification):void

{

var body:Object = notification.getBody();

var type:String = notification.getType();

if(type == "myweb"){

this.facade.registerCommand(AppConstance.LOGIN,loginCommand);

this.facade.registerMediator(new chooseMediator(body));

this.facade.registerMediator(new loginMediator(body));

this.facade.registerProxy(new userProxy());

this.sendNotification(AppConstance.TO_CHOOSE,body)

}else{

trace("不是本站");

}

}

}

}