Android[高级教程] 设计模式之六中介者模式（二）-优快云博客

我们还是接着上一章节的中介者模式，这次我们来重构一下，唐僧只告诉小妖让他的徒弟们来救他，至于小妖通知谁，他不管，反正就是三个徒弟，小妖也想省事，就看见谁就通知谁呗。于是，我们的代码修改成：

public class Monster { private Person person; private String message; public Monster() { } public void setPerson(String name) { if (name.equals("悟空")) { person = new Wukong(); } else if (name.equals("八戒")) { person = new Bajie(); } else if (name.equals("沙僧")){ person = new Shaseng(); } person.setMessage(message); } public String getMessage() { return person.getMessage(); } public void setMessage(String message) { this.message = message; } }首先是小妖的代码，他看见谁就通知谁，至于消息就是唐僧需要转达的消息。接下来看一下唐僧的代码：

public class Tangseng { private Monster monster; public void sendMessage(Monster monster, String message) { this.monster = monster; monster.setMessage(message); } public String getMessage() { return monster.getMessage(); } }里面只有小妖这个对象，他只跟小妖接触，只对小妖说话。然后就是悟空的类了：

public class Wukong implements Person { private String name; private String message; public Wukong() { this.name = "孙悟空"; } @Override public void setMessage(String message) { this.message = message; } @Override public String getMessage() { return name + "收到" + message; } } 这里三个实现类基本完成了，最后就是调用了，最终实现如下：

public class XiyoujiActivity extends Activity { private ListView listView; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); listView = (ListView) findViewById(R.id.listView1); ArrayList<String> lists = new ArrayList<String>(); Tangseng tangseng = new Tangseng(); Monster monster = new Monster(); tangseng.sendMessage(monster,"'徒弟救我'的消息"); monster.setPerson("悟空"); lists.add(tangseng.getMessage()); monster.setPerson("八戒"); lists.add(tangseng.getMessage()); ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, lists); listView.setAdapter(adapter); } }最后运行结果如图：