Android应用中使用Popupmenu

最终效果：

页面布局：

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="fill_parent"
     android:layout_height="fill_parent"
     android:background="#FFFFFF"
     android:orientation="vertical" >

     <RelativeLayout
         android:layout_width="fill_parent"
         android:layout_height="45dp"
         android:background="#303538" >
         <Button
             android:id="@+id/button_showPopup"
             android:layout_width="wrap_content"
             android:layout_height="fill_parent"
             android:layout_alignParentRight="true"
             android:background="#303538"
             android:text="┇"
             android:textColor="#FFFFFF"
             android:textSize="20sp" >
         </Button>
     </RelativeLayout>

 </LinearLayout>

Popupmenu布局（文件在menu目录下）：

 <?xml version="1.0" encoding="utf-8"?>
 <menu xmlns:android="http://schemas.android.com/apk/res/android" >

     <item
         android:id="@+id/about"
         android:orderInCategory="100"
         android:showAsAction="never"
         android:title="关于">
     </item>
     <item
         android:id="@+id/exit"
         android:orderInCategory="100"
         android:showAsAction="never"
         android:title="退出">
     </item>

 </menu>

后台代码：

 package com.wangzhen.popup;

 import android.app.Activity;
 import android.os.Bundle;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.view.Window;
 import android.widget.Button;
 import android.widget.PopupMenu;
 import android.widget.Toast;

 public class Main extends Activity implements OnClickListener,
         android.widget.PopupMenu.OnMenuItemClickListener {
     /** Called when the activity is first created. */
     private Button button_showPopup;

     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         requestWindowFeature(Window.FEATURE_NO_TITLE);
         setContentView(R.layout.main);
         initViews();
     }

     // 初始化控件
     private void initViews() {
         // TODO Auto-generated method stub
         button_showPopup = (Button) findViewById(R.id.button_showPopup);
         button_showPopup.setOnClickListener(this);
     }

     public void onClick(View arg0) {
         // TODO Auto-generated method stub
         switch (arg0.getId()) {
         case R.id.button_showPopup:
             PopupMenu pop = new PopupMenu(this, arg0);
             pop.getMenuInflater().inflate(R.menu.menu, pop.getMenu());
             pop.show();
             pop.setOnMenuItemClickListener(this);
             break;
         }
     }

     public boolean onMenuItemClick(MenuItem arg0) {
         // TODO Auto-generated method stub
         switch (arg0.getItemId()) {
         case R.id.about:
             Toast.makeText(this, "关于", 1000).show();
             break;
         case R.id.exit:
             finish();
             break;
         }
         return false;
     }
 }