和风天气城市列表更新了，把最新数据保存在数据库中是开发和风天气应用一个好方法。不难。
一个类一个文件。
public class Province extends DataSupport { private int id; private String provinceName; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getProvinceName() { return provinceName; } public void setProvinceName(String provinceName) { this.provinceName = provinceName; } }
public class City extends DataSupport { private int id; private String cityName; private int provinceId; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getCityName() { return cityName; } public void setCityName(String cityName) { this.cityName = cityName; } public int getProvinceId() { return provinceId; } public void setProvinceId(int provinceId) { this.provinceId = provinceId; } }
public class County extends DataSupport { private int id; private String countyName; private String weatherId; private int cityId; public int getId(){ return id; } public void setId(int id){ this.id = id; } public String getCountyName(){ return countyName; } public void setCountyName(String countyName){ this.countyName = countyName; } public String getWeatherId(){ return weatherId; } public void setWeatherId(String weatherId){ this.weatherId = weatherId; } public int getCityId(){ return cityId; } public void setCityId(int cityId){ this.cityId = cityId; } }
<litepal> <dbname value="he_weather"/> <version value="1"/> <list> <mapping class="com.heweater.db.Province"/> <mapping class="com.heweater.db.City"/> <mapping class="com.heweater.db.County"/> </list>
import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.view.View; import android.widget.AdapterView; import android.widget.ArrayAdapter; import android.widget.Button; import android.widget.ListView; import android.widget.TextView; import android.widget.Toast; import com.heweater.db.City; import com.heweater.db.County; import com.heweater.db.Province; import org.litepal.crud.DataSupport; import java.util.ArrayList; import java.util.List; import static com.heweater.util.Utility.sendRequestWithHttpURLConnection; public class MainActivity extends AppCompatActivity { private Button createDataBase; private Button readDataBase; public static final int LEVEL_PROVINCE = 0; public static final int LEVEL_CITY = 1; public static final int LEVEL_COUNTY = 2; private ProgressDialog progressDialog; private TextView titleText; private Button backButton; private ListView listView; private ArrayAdapter adapter; private List<String> dataList = new ArrayList<>(); /** * 省列表 */ private List<Province> provinceList; /** * 市列表 */ private List<City> cityList; /** * 县列表 */ private List<County> countyList; /** * 选中的省份 */ private Province selectedProvince; /** * 选中的城市 */ private City selectedCity; /** * 当前选中的级别 */ private int currentLevel; private boolean onlyOnecity; private List<String> provinces; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); backButton = (Button) findViewById(R.id.back_button); titleText = (TextView) findViewById(R.id.title_text); listView = (ListView) findViewById(R.id.country_lvcountry); createDataBase = (Button) findViewById(R.id.createdatabase); readDataBase = (Button) findViewById(R.id.readdata); listView = (ListView) findViewById(R.id.country_lvcountry); adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, dataList); listView.setAdapter(adapter); createDataBase.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { DataSupport.deleteAll("province"); DataSupport.deleteAll("city"); DataSupport.deleteAll("county"); String url = "https://cdn.heweather.com/china-city-list.txt"; sendRequestWithHttpURLConnection(url); } }); readDataBase.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { queryProvinces(); } }); listView.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { if (currentLevel == LEVEL_PROVINCE) { selectedProvince = provinceList.get(position); queryCities(); } else if (currentLevel == LEVEL_CITY) { selectedCity = cityList.get(position ); queryCounties(); }else if(currentLevel == LEVEL_COUNTY){ String weatherId = countyList.get(position ).getWeatherId(); Toast.makeText(MainActivity.this,weatherId,Toast.LENGTH_LONG).show(); } } }); backButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { if ((currentLevel == LEVEL_CITY) || onlyOnecity) { queryProvinces(); } else if (currentLevel == LEVEL_COUNTY) { queryCities(); } } }); } /** * 查询全国所有的省，优先从数据库查询，如果没有查询到再去服务器上查询。 */ private void queryProvinces() { titleText.setText("中国"); backButton.setVisibility(View.GONE); provinceList = DataSupport.findAll(Province.class); if (provinceList.size() > 0) { dataList.clear(); for (Province province : provinceList) { dataList.add(province.getProvinceName()); } adapter.notifyDataSetChanged(); listView.setSelection(0); currentLevel = LEVEL_PROVINCE; } } /** * 查询选中省内所有的市，优先从数据库查询，如果没有查询到再去服务器上查询。 */ private void queryCities() { cityList = DataSupport.where("provinceid = ?", String.valueOf(selectedProvince.getId())).find(City.class); if(cityList.size() == 1){ titleText.setText(selectedProvince.getProvinceName()); backButton.setVisibility(View.VISIBLE); onlyOnecity = true; selectedCity = cityList.get(0); queryCounties(); } else if (cityList.size() > 1) { titleText.setText(selectedProvince.getProvinceName()); backButton.setVisibility(View.VISIBLE); onlyOnecity = false; dataList.clear(); for (City city : cityList) { dataList.add(city.getCityName()); } adapter.notifyDataSetChanged(); listView.setSelection(0); currentLevel = LEVEL_CITY; } } /** * 查询选中市内所有的县，优先从数据库查询，如果没有查询到再去服务器上查询。 */ private void queryCounties() { countyList = DataSupport.where("cityid = ?", String.valueOf(selectedCity.getId())).find(County.class); if(countyList.size() == 1){ String weatherId = countyList.get(0).getWeatherId(); Toast.makeText(MainActivity.this,weatherId,Toast.LENGTH_LONG).show(); }else if (countyList.size() > 1) { titleText.setText(selectedCity.getCityName()); backButton.setVisibility(View.VISIBLE); dataList.clear(); for (County county : countyList) { dataList.add(county.getCountyName()); } adapter.notifyDataSetChanged(); listView.setSelection(0); currentLevel = LEVEL_COUNTY; } } }
public class MyApplication extends LitePalApplication { private static Context context; private static MyApplication instance; @Override public void onCreate(){ context = getApplicationContext(); LitePal.initialize(context); instance = this; } public static MyApplication getInstance() { return instance; } public static Context getContext(){ return context; } }
<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="com.heweater"> <uses-permission android:name="android.permission.INTERNET"/> <application android:name=".MyApplication" android:allowBackup="true" android:icon="@mipmap/ic_launcher" android:label="@string/app_name" android:supportsRtl="true" android:theme="@style/AppTheme"> <activity android:name=".MainActivity"> <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> </application> </manifest>
