菜单（三）二级菜单和标题栏菜单

package com.example.menu2;import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.view.Menu;import android.view.MenuItem;import android.widget.Toast;public class MainActivity extends Activity {@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.main, menu);return true;}@Overridepublic boolean onOptionsItemSelected(MenuItem item) {switch (item.getItemId()) {case R.id.create:Toast.makeText(MainActivity.this, "创建文件", Toast.LENGTH_SHORT).show();break;case R.id.open:Intent intent = new Intent(MainActivity.this, NextActivity.class);item.setIntent(intent);//Toast.makeText(MainActivity.this, "打开文件", Toast.LENGTH_SHORT).show();break;case R.id.load:Toast.makeText(MainActivity.this, "加载", Toast.LENGTH_SHORT).show();break;case R.id.save:Toast.makeText(MainActivity.this, "保存", Toast.LENGTH_SHORT).show();break;default:break;}return super.onOptionsItemSelected(item);}}

主布局文件可以不用管

<RelativeLayout xmlns:android=""xmlns:tools=""android:layout_width="match_parent"android:layout_height="match_parent" ></RelativeLayout>res/menu/main.xml定义菜单<menu xmlns:android="" ><!– orderInCategory菜单顺序类别 –><!– app:showAsAction="never"表示不会在标题栏上面显示 –><itemandroid:id="@+id/menu_settings"android:icon="@drawable/communication"android:orderInCategory="100"android:showAsAction="ifRoom|withText"android:title="菜单设置"><menu><itemandroid:id="@+id/create"android:title="新建文件"></item><itemandroid:id="@+id/open"android:title="打开文件"></item></menu></item><itemandroid:id="@+id/system"android:icon="@drawable/gear"android:orderInCategory="101"android:showAsAction="ifRoom|withText"android:title="用户菜单"><menu><group android:id="@+id/group1" ><itemandroid:id="@+id/load"android:title="加载"></item></group><group android:id="@+id/group2" ><itemandroid:id="@+id/save"android:title="保存"></item></group></menu></item></menu>定义一个菜单跳转的页面<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android=""android:layout_width="match_parent"android:layout_height="match_parent" ><TextViewandroid:id="@+id/textView1"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_alignParentTop="true"android:layout_centerHorizontal="true"android:layout_marginTop="172dp"android:textSize="30sp"android:text="这是跳转的页面" /></RelativeLayout>package com.example.menu2;import android.app.Activity;import android.os.Bundle;public class NextActivity extends Activity{@Overrideprotected void onCreate(Bundle savedInstanceState) {// TODO Auto-generated method stubsuper.onCreate(savedInstanceState);setContentView(R.layout.activity_next);}}

showAsAction指定菜单显示的位置这里是never

如果改为ifRoom|withText，，表示如果actionBar有空间就显示在actionBar而且显示标题

一直开到梦的尽头。你曾经说，