前期准备工作
首先创建XXXWeather项目,具体的我就不多说
这里使用LitePal来管理App的数据库
我们在app/build.gradle文件中增加App需要用到的依赖
implementation 'com.google.android.material:material:1.0.0'
implementation 'org.litepal.android:core:1.4.1'
implementation 'com.squareup.okhttp3:okhttp:3.10.0'
implementation 'com.google.code.gson:gson:2.8.2'
implementation 'com.github.bumptech.glide:glide:4.5.0'
获取城市信息
- 我们获取城市数据是来自郭霖大神给的接口
http://guolin.tech/api/china
,具体情况《第一行代码》第十四章会有讲解。 - 创建db文件夹,在文件夹内部增加三个类,LitePal中的每一个实体类都要继承自DataSupport类的
public class Province extends DataSupport {
private int id;
private String provinceName;
private int provinceCode;
/* public Province(int id, String provinceName, int provinceCode) {
this.id = id;
this.provinceName = provinceName;
this.provinceCode = provinceCode;
}*/
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public int getProvinceCode() {
return provinceCode;
}
public void setProvinceCode(int provinceCode) {
this.provinceCode = provinceCode;
}
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 cityCode;
private int provinceId;
/* public City(int id, String cityName, int cityCode, int provinceId) {
this.id = id;
this.cityName = cityName;
this.cityCode = cityCode;
this.provinceId = 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 getCityCode() {
return cityCode;
}
public void setCityCode(int cityCode) {
this.cityCode = cityCode;
}
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 County(int id, String countyName, String weatherId, int cityId) {
this.id = id;
this.countyName = countyName;
this.weatherId = weatherId;
this.cityId = 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;
}
}
- 接下来就是要配置litepal.xml文件,创建assets文件夹,在目录里创建litepal.xml
<litepal>
<dbname value="xxx_weather" />
<version value="1"/>
<list>
<mapping class="com.xxx.xxxweather.db.Province" />
<mapping class="com.xxx.xxxweather.db.City" />
<mapping class="com.xxx.xxxweather.db.County" />
</list>
</litepal>
- 在AndroidManifest.xml中增加
<application
android:name="org.litepal.LitePalApplication"
遍历省市县数据
- 数据都是从服务端获取的,可以在utils文件夹下增加一个
HttpUtil
类,具体代码如下
public class HttpUtil {
public static void sendOkHttpRequest(String address, okhttp3.Callback callback) {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder().url(address).build();
client.newCall(request).enqueue(callback);
}
}
- 由于返回的城市数据都是json格式,我们在创建一个解析和处理json数据的工具类
Utility
,具体代码如下:
public class Utility {
/**
* 解析服务器返回的省级数据
*/
public static boolean handleProvinceResponse(String response) {
if (!TextUtils.isEmpty(response)) {
try {
JSONArray allProvinces = new JSONArray(response);
for (int i = 0; i < allProvinces.length(); i++) {
JSONObject provinceObject = allProvinces.getJSONObject(i);
Province province = new Province();
province.setProvinceName(provinceObject.getString("name"));
province.setProvinceCode(provinceObject.getInt("id"));
province.save();
}
return true;
} catch (JSONException e) {
e.printStackTrace();
}
}
return false;
}
/**
* 解析服务器返回的市级数据
*/
public static boolean handleCityResponse(String response, int provinceId) {
if (!TextUtils.isEmpty(response)) {
try {
JSONArray allCities = new JSONArray(response);
for (int i = 0; i < allCities.length(); i++) {
JSONObject cityObject = allCities.getJSONObject(i);
City city = new City();
city.setCityName(cityObject.getString("name"));
city.setCityCode(cityObject.getInt("id"));
city.setProvinceId(provinceId);
city.save();
}
return true;
} catch (JSONException e) {
e.printStackTrace();
}
}
return false;
}
/**
* 解析服务器返回的县级数据
*/
public static boolean handleCountyResponse(String response, int cityId) {
if (!TextUtils.isEmpty(response)) {
try {
JSONArray allCounties = new JSONArray(response);
for (int i = 0; i < allCounties.length(); i++) {
JSONObject countyObject = allCounties.getJSONObject(i);
County county = new County();
county.setCountyName(countyObject.getString("name"));
county.setWeatherId(countyObject.getString("weather_id"));
county.setCityId(cityId);
county.save();
}
return true;
} catch (JSONException e) {
e.printStackTrace();
}
}
return false;
}
}
- 现在我们就开始写界面布局了,由于城市三级列表我们在后面还要使用,因此就不写成Activity了,写在碎片Fragment里面,方便在后面使用的时候直接在布局里面引用碎片。
在layout文件夹里创建choose_area.xml文件
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:background="#fff"
android:layout_width="match_parent"
android:layout_height="match_parent">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="@color/cardview_dark_background">
<TextView
android:id="@+id/title"
android:text="中国"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="25dp"
android:layout_centerHorizontal="true"
android:textColor="#fff"
android:textSize="20sp"/>
<ImageButton
android:id="@+id/back"
android:layout_width="25dp"
android:layout_height="25dp"
android:layout_alignParentLeft="true"
android:layout_alignParentBottom="true"
android:layout_marginBottom="5dp"
android:layout_marginLeft="10dp"
android:background="@drawable/ic_back" />
</RelativeLayout>
<ListView
android:id="@+id/list"
android:layout_width="match_parent"
android:layout_height="match_parent">
</ListView>
</LinearLayout>
- 接下来就是创建用于遍历省市县数据的碎片文件了。新建ChooseAreaFragment继承自Fragment
public class ChooseAreaFragment extends Fragment {
public static final int LEVEL_PROVINCE = 0;
public static final int LEVEL_CITY = 1;
public static final int LEVEL_COUNTY = 2;
private ProgressBar mProgressBar;
private TextView mTitleText;
private ImageButton mBackButton;
private ListView mListView;
private ArrayAdapter<String> mAdapter;
private List<String> dataList = new ArrayList<>();
private List<Province> mProvinceList;
private List<City> mCityList;
private List<County> mCountyList;
private Province selectedProvice;
private City selectedCity;
private int currentLevel; //当前选中的级别
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.choose_area, container, false);
mTitleText = view.findViewById(R.id.title);
mBackButton = view.findViewById(R.id.back);
mListView = view.findViewById(R.id.list);
mAdapter = new ArrayAdapter<>(getContext(), android.R.layout.simple_list_item_1, dataList);
mListView.setAdapter(mAdapter);
return view;
}
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
mListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int pos, long id) {
if (currentLevel == LEVEL_PROVINCE) {
selectedProvice = mProvinceList.get(pos);
queryCities();
} else if (currentLevel == LEVEL_CITY) {
selectedCity = mCityList.get(pos);
queryCounties();
} else if (currentLevel == LEVEL_COUNTY) {
String weatherId = mCountyList.get(pos).getWeatherId();
String countyName = mCountyList.get(pos).getCountyName();
if (getActivity() instanceof MainActivity) {
Intent intent = new Intent(getActivity(), WeatherActivity.class);
intent.putExtra("weather_id", weatherId);
intent.putExtra("county_name",countyName);
startActivity(intent);
getActivity().finish();
} else if (getActivity() instanceof WeatherActivity) {
WeatherActivity activity = (WeatherActivity) getActivity();
activity.drawerLayout.closeDrawers();
activity.mSwipeRefresh.setRefreshing(true);
activity.requestWeather(weatherId);
}
}
}
});
mBackButton.setOnClickListener(new View.OnClickListener(){
@Override
public void onClick(View view) {
if (currentLevel == LEVEL_COUNTY) {
queryCities();
} else if (currentLevel == LEVEL_CITY) {
queryProvinces();
}
}
});
queryProvinces();
}
private void queryProvinces() {
mTitleText.setText("中国");
mBackButton.setVisibility(View.GONE);
mProvinceList = DataSupport.findAll(Province.class);
if (mProvinceList.size() > 0) {
dataList.clear();
for (Province province : mProvinceList) {
dataList.add(province.getProvinceName());
}
mAdapter.notifyDataSetChanged();
mListView.setSelection(0);
currentLevel = LEVEL_PROVINCE;
} else {
String address = "http://guolin.tech/api/china";
queryFromServer(address, "province");
}
}
private void queryCities() {
mTitleText.setText(selectedProvice.getProvinceName());
mBackButton.setVisibility(View.VISIBLE);
mCityList = DataSupport.where("provinceId = ?", String.valueOf(selectedProvice.getId())).find(City.class);
if (mCityList.size() > 0) {
dataList.clear();
for (City city : mCityList) {
dataList.add(city.getCityName());
}
mAdapter.notifyDataSetChanged();
mListView.setSelection(0);
currentLevel = LEVEL_CITY;
} else {
int provinceCode = selectedProvice.getProvinceCode();
String address = "http://guolin.tech/api/china/" + provinceCode;
queryFromServer(address, "city");
}
}
private void queryCounties() {
mTitleText.setText(selectedCity.getCityName());
mBackButton.setVisibility(View.VISIBLE);
mCountyList = DataSupport.where("cityId = ?", String.valueOf(selectedCity.getId())).find(County.class);
if (mCountyList.size() > 0) {
dataList.clear();
for (County county : mCountyList) {
dataList.add(county.getCountyName());
}
mAdapter.notifyDataSetChanged();
mListView.setSelection(0);
currentLevel = LEVEL_COUNTY;
} else {
int provinceCode = selectedProvice.getProvinceCode();
int cityCode = selectedCity.getCityCode();
String address = "http://guolin.tech/api/china/" + provinceCode + "/" + cityCode;
queryFromServer(address, "county");
}
}
//根据传入的地址和服务类型从服务器上查询省市县数据
private void queryFromServer(String address, final String type) {
HttpUtil.sendOkHttpRequest(address, new okhttp3.Callback() {
@Override
public void onResponse(Call call, Response response) throws IOException {
String responseText = response.body().string();
boolean result = false;
if ("province".equals(type)) {
result = Utility.handleProvinceResponse(responseText);
} else if ("city".equals(type)) {
result = Utility.handleCityResponse(responseText, selectedProvice.getId());
} else if ("county".equals(type)) {
result = Utility.handleCountyResponse(responseText, selectedCity.getId());
}
if (result) {
getActivity().runOnUiThread(new Runnable() {
@Override
public void run() {
//closeProgressBar();
if ("province".equals(type)) {
queryProvinces();
} else if ("city".equals(type)) {
queryCities();
} else if ("county".equals(type)) {
queryCounties();
}
}
});
}
}
@Override
public void onFailure(Call call, IOException e) {
//通过
getActivity().runOnUiThread(new Runnable() {
@Override
public void run() {
//closeProgressBar();
Toast.makeText(getContext(), "加载失败", Toast.LENGTH_SHORT).show();
}
});
}
});
}
}
- 我们将碎片添加到活动中它才能显示,因此我们要向activity_main.xml中添加如下代码:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<fragment
android:id="@+id/choose_area_fragment"
android:name="com.atwang.antaoweather.activity.ChooseAreaFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
</FrameLayout>
当然这里还没完,还有一些后续收尾工作。
后续工作
- 我们刚才在碎片的布局中自定义了一个标题栏,现在将原生标题栏去掉,在styles.xml中修改
<style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
- 最最重要的是访问网络权限,它可不能忘,在AndroidManifest.xml中添加
<uses-permission android:name="android.permission.INTERNET" />
你以为这样就结束了吗?
- Android高版本访问网络总是会失败,因此我创建了xml文件夹,在里面增加了
network-security-config.xml
文件。
<?xml version="1.0" encoding="utf-8"?>
<network-security-config>
<base-config cleartextTrafficPermitted="true" />
</network-security-config>
同时在在AndroidManifest.xml中<application
下添加
android:networkSecurityConfig="@xml/network_security_config"
- 这次是结束了,来看图
请忽略这个字体