“移动应用开发”实验报告---天气预报

“移动应用开发”实验报告

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数据代码即运行结果截图

一、整体架构、

本次实验我分配的任务是查看某地区天气的活动代码编写和添加权限与

注册的相关代码，具体的过程在下面：

1、活动（Activity）整体结构

2、设计界面（layout）整体结构

二、数据代码

本次作业（天气预报）的设计界面效果图如下：

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接着需要编写遍历省市县的活动，即MainActivity。代码如下：

package com.example.chen.weatherforecast;

import android.app.ProgressDialog;

import android.content.Intent;

import android.content.SharedPreferences;

import android.preference.PreferenceManager;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.text.TextUtils;

import android.view.View;

import android.view.Window;

import android.widget.AdapterView;

import android.widget.ArrayAdapter;

import android.widget.ListView;

import android.widget.TextView;

import android.widget.Toast;

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import java.util.ArrayList;

import java.util.List;

import DB.CoolWeatherDB;

import model.City;

import model.County;

import model.Province;

import unity.HttpCallbackLinster;

import unity.HttpUtil;

import util.Utility;

public class MainActivity extends AppCompatActivity {

public static final int LEVEL_PROVINCE = 0; //省级

public static final int LEVEL_CITY = 1; //市级

public static final int LEVEL_COUNTY = 2; //县级

private ProgressDialog progressDialog;

private ListView listView; //显示省市县的数据

private TextView title_text; //标题内容

private ArrayAdapter adapter; //listView 的适配器

private List datalist = new ArrayList();

private List provinceList; //省列表

private List cityList; //市列表

private List countyList; //县列表

private CoolWeatherDB coolWeatherDB;

private Province selectProvince; //选中的省

private City selectCity; //选中的市

private int currentLevel; //选中的县

private Boolean isFromWeatherActivity;

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

requestWindowFeature(Window.FEATURE_NO_TITLE);

setContentView(https://www.360docs.net/doc/d415885091.html,yout.activity_main);

isFromWeatherActivity =

getIntent().getBooleanExtra("from_weather_activity",false);

SharedPreferences pref =

PreferenceManager.getDefaultSharedPreferences(MainActivity.this);

if(pref.getBoolean("city_cheeked",false)&& !isFromWeatherActivity ) { Intent intent = new Intent(this,LookWeather.class);

startActivity(intent);

finish();

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} listView = (ListView)findViewById(R.id.list_view);

title_text = (TextView)findViewById(R.id.title_text);

adapter = new

ArrayAdapter(MainActivity.this,https://www.360docs.net/doc/d415885091.html,yout.simple_list_item_1, datalist);

listView.setAdapter(adapter);

coolWeatherDB = CoolWeatherDB.getInstance(this);

listView.setOnItemClickListener(new

AdapterView.OnItemClickListener() {

@Override

public void onItemClick(AdapterView parent, View view, int position, long id) {

if(currentLevel == LEVEL_PROVINCE) {

selectProvince = provinceList.get(position);

querCity(); //选中省，则查找该省的市

} else if(currentLevel == LEVEL_CITY) {

selectCity = cityList.get(position);

querCounty(); //选中市，则查找该市的县

} else if(currentLevel == LEVEL_COUNTY) //选中县，则查找该县所对应的

天气

{

String countyCode = countyList.get(position).getCountycode();

Intent intent = new Intent(MainActivity.this,LookWeather.class); intent.putExtra("county_code",countyCode);

startActivity(intent);

finish();

} } });

querProvince();

} //查找省，如果在数据库中没有找到，则在服务器上找

private void querProvince() {

provinceList = coolWeatherDB.loadProvince();

if(provinceList.size() > 0) {

datalist.clear();

for(Province province : provinceList) {

datalist.add(province.getProvinceName());

}

adapter.notifyDataSetChanged();

listView.setSelection(0);

title_text.setText("中国");

currentLevel = LEVEL_PROVINCE;

} else

{ //在服务器上查找

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querfromServer(null, "province");

} } //查找市，如果在数据库中没有找到，则在服务器上找

private void querCity() {

cityList = coolWeatherDB.loadCity(selectProvince.getId());

if(cityList.size() > 0) {

datalist.clear();

for(City city : cityList) {

datalist.add(city.getCityName());

}

adapter.notifyDataSetChanged();

listView.setSelection(0);

title_text.setText(selectProvince.getProvinceName());

currentLevel = LEVEL_CITY;

} else

{ querfromServer(selectProvince.getProvinceCode(),"city");

} } //查找县，如果在数据库中没有找到，则在服务器上找

private void querCounty() {

countyList = coolWeatherDB.loadCounty(selectCity.getId());

if(countyList.size() > 0) {

datalist.clear();

for(County county : countyList) {

datalist.add(county.getCountyName());

} adapter.notifyDataSetChanged();

listView.setSelection(0);

title_text.setText(selectCity.getCityName());

currentLevel = LEVEL_COUNTY;

} else

{ querfromServer(selectCity.getCityCode(),"county");

} } //根据传入的代号和类型在服务器上查找数据

private void querfromServer(final String code,final String type)

{ String address;

if(!TextUtils.isEmpty(code)) { address =

"https://www.360docs.net/doc/d415885091.html,/data/list3/city" + code +".xml";

} else

{ address = "https://www.360docs.net/doc/d415885091.html,/data/list3/city.xml";

} showProgressDialog();

HttpUtil.sendRequstWithURLConnection(address, new

HttpCallbackLinster() {

@Override

public void onFinish(String response) { boolean result = false;

if ("province".equals(type)) { result =

Utility.handleProvince(coolWeatherDB, response);

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} else if ("city".equals(type)) { result =

Utility.handleCity(coolWeatherDB, response, selectProvince.getId());

} else if ("county".equals(type)) { result =

Utility.handleCounty(coolWeatherDB, response, selectCity.getId());

} if (result) { runOnUiThread(new Runnable() { @Override

public void run() { closeProgressDialog();

if ("province".equals(type)) { querProvince();

} else if ("city".equals(type)) { querCity();

} else if ("county".equals(type)) { querCounty();

} } });

} } public void onError(Exception e) { runOnUiThread(new Runnable() { @Override

public void run() { closeProgressDialog();

Toast.makeText(MainActivity.this,"加载失败

",Toast.LENGTH_SHORT).show();

} });

} });

} private void showProgressDialog() { if(progressDialog == null)

{ progressDialog = new ProgressDialog(MainActivity.this);

progressDialog.setMessage("正在加载...");

progressDialog.setCanceledOnTouchOutside(false);

} progressDialog.show();

} private void closeProgressDialog() {

if(progressDialog != null) {

progressDialog.dismiss();

} } //捕获返回键，来判断此时应直接返回省，市列表还是返回到显示天气的页面public void onBackPressed() {

if(currentLevel == LEVEL_COUNTY) {

querCity();

}else if(currentLevel == LEVEL_CITY) {

querProvince();

}else { if (isFromWeatherActivity) {

Intent intent = new Intent(MainActivity.this, LookWeather.class); startActivity(intent);

} finish();

} } }

还要加上权限声明和注册Activity，即AndroidManifest.xml的代码：

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package="com.example.chen.weatherforecast">

android:allowBackup="true"

android:icon="@mipmap/ic_launcher"

android:label="@string/app_name"

android:roundIcon="@mipmap/ic_launcher_round"

android:supportsRtl="true"

android:theme="@style/AppTheme">

2、获取省、市、县的天气数据

在Utility类中添加解析JSON数据与处理。（代码请见前面Utility类的代码）。

接着在Layout写LookWeatherActivity的布局。

android:orientation="vertical" android:layout_width="match_parent"

android:layout_height="match_parent">

android:layout_width="match_parent"

android:layout_height="50dp"

android:background="#0099ff">

android:id="@+id/switch_bt"

android:layout_width="40dp"

android:layout_height="40dp"

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android:layout_marginStart="10dp"

android:layout_centerVertical="true"

/>

android:id="@+id/weather_title"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:textSize="24sp"

android:textColor="#FFFFFF"

android:layout_centerInParent="true"

/>

android:id="@+id/refresh"

android:layout_width="30dp"

android:layout_height="30dp"

android:layout_alignParentEnd="true"

android:layout_marginRight="10dp"

android:layout_centerInParent="true"/>

android:background="#99cccc"

android:layout_width="match_parent"

android:layout_height="match_parent">

android:id="@+id/punish_time"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignParentEnd="true"

android:textSize="28sp"

android:layout_marginTop="20dp"

android:layout_marginEnd="20dp"

/>

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_centerInParent="true"

android:orientation="vertical">

android:id="@+id/data"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:gravity="center"

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android:textSize="25sp"

/>

android:id="@+id/weather_detail"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:gravity="center"

android:textSize="35sp"

/>

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:orientation="horizontal">

android:id="@+id/low_temp"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_vertical"

android:textSize="30sp"

/>

android:id="@+id/temp_line"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_vertical"

android:textSize="30sp"

android:text="~"/>

android:id="@+id/high_temp"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_gravity="center_vertical"

android:textSize="30sp"

/>

布局效果图如下：中间部分显示天气情况，左上角的按钮功能是回退，右上角的按

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钮功能是刷新（同步最新天气信息）。

接着写LookWeather的Activity。

package com.example.chen.weatherforecast;

import android.content.Intent;

import android.content.SharedPreferences;

import android.os.Bundle;

import android.preference.PreferenceManager;

import android.support.v7.app.AppCompatActivity;

import android.text.TextUtils;

import android.view.View;

import android.view.Window;

import android.widget.Button;

import android.widget.TextView;

import unity.HttpCallbackLinster;

import unity.HttpUtil;

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import util.Utility;

/**

* Created by Administrator on 2018/12/29.

*/

public class LookWeather extends AppCompatActivity implements

View.OnClickListener{

private TextView title;

private TextView punish_time;

private TextView data;

private TextView detail;

private TextView low_temp;

private TextView high_temp;

private Button switch_bt;

private Button refresh;

@Override

protected void onCreate(Bundle savedInstanceState)

{ super.onCreate(savedInstanceState);

requestWindowFeature(Window.FEATURE_NO_TITLE);

//setContentView(https://www.360docs.net/doc/d415885091.html,yout.cheeked_weather);

setContentView(https://www.360docs.net/doc/d415885091.html,yout.look_weather_activity);

findviews();

String countyCode = getIntent().getStringExtra("county_code");

if(!TextUtils.isEmpty(countyCode)) {

queryWeatherCode(countyCode);

} else

{ showWeather();

} switch_bt.setOnClickListener(this);

refresh.setOnClickListener(this);

} private void queryWeatherCode(String countyCode) { String address = "https://www.360docs.net/doc/d415885091.html,/data/list3/city" + countyCode +".xml";

queryFromService(address, "countyCode");

} private void queryInfo(String weatherCode) { String address =

"https://www.360docs.net/doc/d415885091.html,/data/cityinfo/" + weatherCode +".html";

queryFromService(address,"weatherCode");

} private void queryFromService(final String address, final String type) {

HttpUtil.sendRequstWithURLConnection(address, new

HttpCallbackLinster() {

@Override

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public void onFinish(String response) { if("countyCode".equals(type)) { if(!TextUtils.isEmpty(response)) { String[] array = response.split("\\|");

if(array != null && array.length == 2) { String weatherCode = array[1];

queryInfo(weatherCode);

} } }else if("weatherCode".equals(type)) {

Utility.handleWeatherResorce(LookWeather.this, response);

runOnUiThread(new Runnable() { @Override

public void run() { showWeather();

} });

} } @Override

public void onError(Exception e) { runOnUiThread(new Runnable() { @Override public void run() { punish_time.setText("更新失败");

} });

} });

} private void showWeather() {

SharedPreferences pref =

PreferenceManager.getDefaultSharedPreferences(LookWeather.this);

title.setText(pref.getString("city_name",""));

punish_time.setText("今天"+pref.getString("punish_time","")+"发布");

data.setText(pref.getString("data",""));

detail.setText(pref.getString("weather",""));

low_temp.setText(pref.getString("low_temp",""));

high_temp.setText(pref.getString("high_temp",""));

} private void findviews() { title =

(TextView)findViewById(R.id.weather_title);

punish_time = (TextView)findViewById(R.id.punish_time);

data = (TextView)findViewById(R.id.data);

detail = (TextView)findViewById(R.id.weather_detail);

low_temp = (TextView)findViewById(R.id.low_temp);

high_temp = (TextView)findViewById(R.id.high_temp);

switch_bt = (Button)findViewById(R.id.switch_bt);

refresh = (Button)findViewById(R.id.refresh);

} @Override

public void onClick(View v) { switch (v.getId()) {

case R.id.switch_bt:

Intent intent = new Intent(LookWeather.this,MainActivity.class);

intent.putExtra("from_weather_activity", true);

startActivity(intent);

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finish();

break ;

case R.id.refresh : title .setText("正在同步中...");

SharedPreferences sp =

PreferenceManager.getDefaultSharedPreferences (this );

String weatherCode = sp.getString("city_code","");

if (! TextUtils.isEmpty (weatherCode)) { queryInfo(weatherCode); } break ;

default : break ;

} } }

这个Activity 同样需要注册，注册代码请见上文的AndroidManifest.xml 。

三、运行结果截图

天气预报APP 的界面如图所示：

以查看宁波的天气为例，先在最上级目录中找到浙江省，点击进入下一级目录：点击宁波市，进入选择县（区）的目录：

选择第一个（宁波市区），点击查看宁波的天气：

若想查看其它城市的天气，则后退选择其他省份的其他城市即可。例如想查看杭州

的天气：

错误总结

这个活动中的代码比较长，在onCreate()方法中先是去获取一些控件的实例，然后会尝试从本

地缓存中读取天气数据。第一次是没有缓存的，因此会从Intent中取出天气id，并调用requestWeather()方法来从服务器请求天气数据。出现空数据的界面看上去会很奇怪的。

在这次作业的过程当中缓存没存好，出现下一次再进入WeatherActivity时，再次发起网络请求了。

Android studio软件的错误提示是最多的，一次性没完成就保存后工程目录下的文件，下次打开出

现一大堆红色错误提示，由于英语水平有限，有些问题真的不知道怎么解决。

个人心得体会

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