ANDROID笔记：利用XML布局文件生成Menu

package com.example.android_menu;

import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.widget.TextView;

public class MyMenuActivity extends Activity {
    TextView textView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.contextmenuactivity);
        textView = (TextView) findViewById(R.id.itemtext);
    }

    /**
     * 点击菜单按键时调用的函数
     */
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // 菜单加载器
        MenuInflater menuInflater = new MenuInflater(getApplicationContext());
        menuInflater.inflate(R.menu.mymenu, menu);
        return super.onCreateOptionsMenu(menu);
    }

    /**
     * 响应菜单动作的回调函数
     */
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        //得到Id
        switch (item.getItemId()) {
        case R.id.font10sp:
            textView.setTextSize(10);
            break;
        case R.id.font20sp:
            textView.setTextSize(20);
            break;
        case R.id.font30sp:
            textView.setTextSize(30);
            break;
        case R.id.fontblue:
            textView.setTextColor(Color.BLUE);
            break;
        case R.id.fontgreen:
            textView.setTextColor(Color.GREEN);
            break;
        case R.id.fontred:
            textView.setTextColor(Color.RED);
            break;
        }
        return super.onOptionsItemSelected(item);
    }
}

res/menu/mymenu.xml

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

    <item
        android:id="@+id/fontsize"
        android:title="设置字体大小">
        <menu>
 <!-- 单选 -->
            <group android:checkableBehavior="single" >
                <item
                    android:id="@+id/font10sp"
                    android:title="10sp">
                </item>
                <item
                    android:id="@+id/font20sp"
                    android:title="20sp">
                </item>
                <item
                    android:id="@+id/font30sp"
                    android:title="30sp">
                </item>
            </group>
        </menu>
    </item>
    <item
        android:id="@+id/selectnull"
        android:title="空白菜单"/>
    <item
        android:id="@+id/fontcolor"
        android:title="设置字体颜色">
        <menu>
 <!-- 多选 -->
            <group android:checkableBehavior="all" >
                <item
                    android:id="@+id/fontred"
                    android:title="红色">
                </item>
                <item
                    android:id="@+id/fontgreen"
                    android:title="绿色">
                </item>
                <item
                    android:id="@+id/fontblue"
                    android:title="蓝色">
                </item>
            </group>
        </menu>
    </item>

</menu>

点击Menu按键就会在屏幕底部弹出Menu