该程序主要使用 中央气象局 省份 城市数据库为基础 进行读取
城市数据库下载 http://download.csdn.net/download/xianqiang1/3896880 感谢该兄弟的分享
下载的数据库 db_weather.db 放到sdcard/weather 目录下面 方便后续操作
为了更好的了解数据库,使用 SQLite Database Browser 可以打开数据库 查看数据 和表等信息,如下
了解了表的构成可以实现操作了
androidManifest.xml
配置文件声明 添加操作sdcard 权限
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.cityselection" android:versionCode="1" android:versionName="1.0" > <uses-sdk android:minSdkVersion="8" /> <!-- sdcard操作允许 --> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/> <application android:icon="@drawable/ic_launcher" android:label="@string/app_name" > <activity android:name=".City_SelectionActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest>
布局文件main.xml
主要使用两个 spinner 分别实现城市 省份的选择
<?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:orientation="vertical" > <TextView android:text="省份/直辖市" android:textSize="20dp" android:textStyle="bold" android:layout_width="fill_parent" android:layout_height="wrap_content" /> <Spinner android:id="@+id/provinces" android:layout_width="fill_parent" android:layout_height="wrap_content" /> <TextView android:text="市/县" android:textSize="20dp" android:textStyle="bold" android:layout_width="fill_parent" android:layout_height="wrap_content" /> <Spinner android:id="@+id/city" android:layout_width="fill_parent" android:layout_height="wrap_content" /> </LinearLayout>
主程序City_SelectionActivity.java
package com.cityselection; import java.io.File; import java.util.ArrayList; import java.util.List; import android.app.Activity; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.AdapterView.OnItemSelectedListener; import android.widget.ArrayAdapter; import android.widget.Spinner; import android.widget.Toast; public class City_SelectionActivity extends Activity { /** Called when the activity is first created. */ private File f = new File("/sdcard/weather/db_weather.db"); //数据库文件 private Spinner province; //省份spinner private Spinner city; //城市spinner private List<String> proset=new ArrayList<String>();//省份集合 private List<String> citset=new ArrayList<String>();//城市集合 private int pro_id; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); province=(Spinner)findViewById(R.id.provinces); ArrayAdapter<String> pro_adapter=new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item,getProSet()); province.setAdapter(pro_adapter); province.setOnItemSelectedListener(new SelectProvince()); city=(Spinner)findViewById(R.id.city); city.setOnItemSelectedListener(new SelectCity()); } //选择改变状态 class SelectProvince implements OnItemSelectedListener{ public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { // TODO Auto-generated method stub //获得省份ID pro_id=position; city.setAdapter(getAdapter()); } public void onNothingSelected(AdapterView<?> arg0) { // TODO Auto-generated method stub } } //城市 选择改变状态 class SelectCity implements OnItemSelectedListener{ public void onItemSelected(AdapterView<?> parent, View view, int position, long id) { // TODO Auto-generated method stub String cityname=parent.getItemAtPosition(position).toString(); //选择提示 Toast.makeText(getApplicationContext(), cityname+" "+getCityNum(position), 2000).show(); } public void onNothingSelected(AdapterView<?> arg0) { // TODO Auto-generated method stub } } /** * 返回 省份集合 */ public List<String> getProSet(){ //打开数据库 SQLiteDatabase db1 = SQLiteDatabase.openOrCreateDatabase(f, null); Cursor cursor=db1.query("provinces", null, null, null, null, null, null); while(cursor.moveToNext()){ String pro=cursor.getString(cursor.getColumnIndexOrThrow("name")); proset.add(pro); } cursor.close(); db1.close(); return proset; } /** * 返回 城市集合 */ public List<String> getCitSet(int pro_id){ //清空城市集合 citset.clear(); //打开数据库 SQLiteDatabase db1 = SQLiteDatabase.openOrCreateDatabase(f, null); Cursor cursor=db1.query("citys", null, "province_id="+pro_id, null, null, null, null); while(cursor.moveToNext()){ String pro=cursor.getString(cursor.getColumnIndexOrThrow("name")); citset.add(pro); } cursor.close(); db1.close(); return citset; } /** * 返回适配器 */ public ArrayAdapter<String> getAdapter(){ ArrayAdapter<String> adapter1=new ArrayAdapter(this, android.R.layout.simple_spinner_item,getCitSet(pro_id)); return adapter1; } /** * 返回城市编号 以便调用天气预报api */ public long getCityNum(int position){ SQLiteDatabase db1 = SQLiteDatabase.openOrCreateDatabase(f, null); Cursor cursor=db1.query("citys", null, "province_id="+pro_id, null, null, null, null); cursor.moveToPosition(position); long citynum=Long.parseLong(cursor.getString(cursor.getColumnIndexOrThrow("city_num"))); cursor.close(); db1.close(); return citynum; } }
实现结果: