Android Popup Menu的使用方法

1. 概述

弹出式菜单是和某个View关联在一起的，Android会根据这个View的位置，自动确定弹出式菜单的显示位置。

创建弹出式菜单的步骤如下：

• PopupMenu popupMenu = new PopupMenu(context, view);
• Menu menu = popupMenu.getMenu();
• popupMenu.getMenuInflater().inflate(resId, menu);
• popupMenu.setOnMenuItemClickListener(xxxxx);
• popupMenu.show();
  

2. 示例

2.1 Java代码

package com.example.hellopopupmenu;

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

public class MainActivity extends Activity {

	private Button button = null;
	private Toast toast = null;
	
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.hello_popup_menu_main);

        button = (Button) this.findViewById(R.id.button);
        button.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				showPopupMenu();
			}
        	
        });
        
    }


	private void showPopupMenu() {
		PopupMenu popupMenu = new PopupMenu(this, button);
		Menu menu = popupMenu.getMenu();
		MenuInflater inflater = popupMenu.getMenuInflater();
		inflater.inflate(R.menu.popup_menu, menu);
		popupMenu.setOnMenuItemClickListener(new OnMenuItemClickListener() {

			@Override
			public boolean onMenuItemClick(MenuItem item) {
				switch (item.getItemId()) {
				case R.id.item01:
					showToast("item01");
					return true;
				case R.id.item02:
					showToast("item02");
					return true;
				case R.id.item03_01:
					showToast("item03_01");
					return true;
				case R.id.item03_02:
					showToast("item03_02");
					return true;
				default:
					return false;
				}
			}
			
		});
		
		popupMenu.show();
	}


	private void showToast(String string) {
		if (toast == null) {
			toast = Toast.makeText(this, "", Toast.LENGTH_SHORT);
		}
		
		toast.setText(string);
		toast.show();
	}
}

2.2 布局文件

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

<!-- hello_popup_menu_main.xml -->

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    
    <Button
        android:id="@+id/button"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/button_text"/>
</LinearLayout>

2.3 菜单资源

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

<!-- popup_menu.xml -->

<menu xmlns:android="http://schemas.android.com/apk/res/android" >
    <item
        android:id="@+id/item01"
        android:title="@string/item01"/>
    
    <item 
        android:id="@+id/item02"
        android:title="@string/item02"/>

    <item
        android:id="@+id/item03"
        android:title="@string/item03">
        
	    <menu>
			<item
		        android:id="@+id/item03_01"
		        android:title="@string/item03_01"/>
		    <item
		        android:id="@+id/item03_02"
		        android:title="@string/item03_02"/>
		</menu>
		
	</item>
	
</menu>

2.4 字符串资源

<string name="button_text">Show a PopupMenu</string>
<string name="item01">item01</string>
<string name="item02">item02</string>
<string name="item03">item03</string>
<string name="item03_01">item03_01</string>
<string name="item03_02">item03_02</string>