(二)SecondActivity.java

package com.example.second;import java.util.ArrayList;import java.util.List;import android.os.Bundle;import android.app.Activity;import android.content.Intent;import android.view.Menu;import android.view.MenuItem;import android.widget.ArrayAdapter;import android.widget.ListView;public class SecondActivity extends Activity {//1.定义菜单项,类型为全局静态的整数final static int menu_forecast=Menu.FIRST;final static int menu_history=Menu.FIRST+1;final static int menu_setting=Menu.FIRST+2;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_second);}//onCreate    //2.菜单第一次生成时所要执行的内容，且只执行一次@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.//getMenuInflater().inflate(R.menu.second, menu);//把每一个菜单项加入到菜单对象menu中menu.add(0,menu_forecast, 0, "天气预报").setIcon(android.R.drawable.alert_light_frame);        //加系统中（android.R）的图片menu.add(0, menu_history, 1, "历史数据").setIcon(android.R.drawable.ic_lock_silent_mode);menu.add(0, menu_setting, 2, "系统设置").setIcon(android.R.drawable.btn_dropdown);return true;}//onCreateOptionsMenu    //3.用户每次选择菜单时都执行；判断用户选了哪个菜单，从而做出跳转@Overridepublic boolean onOptionsItemSelected(MenuItem item) {// TODO Auto-generated method stub//return super.onOptionsItemSelected(item);switch(item.getItemId()){case menu_forecast:System.out.println("menu_forecast");Intent in4=new Intent(SecondActivity.this,ForecastActivity.class);startActivity(in4);return true;case menu_history:System.out.println("menu_history");Intent in5=new Intent(SecondActivity.this,HistoryActivity.class);startActivity(in5);return true; case menu_setting:System.out.println("menu_setting");Intent in6=new Intent(SecondActivity.this,SettingActivity.class);startActivity(in6);return true;}//switchreturn false;}//onOptionsItemSelected//4.对应于onCreateOptionsMenu方法@Overridepublic boolean onPrepareOptionsMenu(Menu menu) {// TODO Auto-generated method stub//return super.onPrepareOptionsMenu(menu);return true;}}//class SecondActivity