Android Studio 使用GET方式获取天气_android studio 天气widget

 手机登录校园网极其费劲，时常打不开校园网的登录页面，打开了也存不住账号密码

为了不要每次都输一遍，打算做个手动登录校园网的APP

经过抓包发现校园网只需通过get请求发送ip，账号和密码即可登录成功，就在某篇文章里找到了这个GET获取天气的方法，改过许多遍，在我目前的JDK8环境下能跑起来

注意，Android中访问网络需要开启子线程来完成

package com.example.myapplication;
 
import android.app.Notification;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.os.Looper;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.PopupWindow;
import android.widget.TextView;
import android.widget.Toast;
 
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.NotificationCompat;
 
public class MainActivity extends AppCompatActivity {
    private TextView tvContent;
    private Handler mHandler = new Handler(Looper.myLooper()){
 
    public void handleMessage(@NonNull Message msg){
        tvContent = findViewById(R.id.tv_content);
        super.handleMessage(msg);
 
        if(msg.what==0){
            String strData = (String)msg.obj;
            tvContent.setText(strData);
            Toast.makeText(MainActivity.this,"主线程收到网络消息啦！",Toast.LENGTH_SHORT).show();
        }
    }
};
 
    private String getStringFormNet(){
        //从网络上获取字符串
        return NetUtil.getWeatherOfCity("赣州");
    }
 
    public void start(View view){
        //做一个耗时任务
        new Thread(new Runnable(){
            @Override
            public void run(){
                String stringFormNet = getStringFormNet();
 
                //使用handler来发送消息
                Message message = new Message();
                message.what = 0;//用于区分是谁发的消息
                message.obj = stringFormNet;
                mHandler.sendMessage(message);
 
            }
        }).start();
        Toast.makeText(MainActivity.this,"开启子线程请求网络！",Toast.LENGTH_SHORT).show();
    }
 
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
 
 
        start(findViewById(R.id.tv_content));//tvcontent是一个textview
        Log.d("success", "成功启动 ");
 
        setContentView(R.layout.activity_main);
 
 
 
 
 
 
}
 

MainActivity.java

使用geteather of city函数完成对城市的传参，并且拼接get请求的url传入Netutil函数进行http请求

package com.example.myapplication;
 
import android.util.Log;
 
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.ProtocolException;
import java.net.URL;
 
public class NetUtil{
    public static String BASE_URL="https://v0.yiketianqi.com/free/day";
    public static String APP_ID="14846972";
    public static String APP_SECRET="Guya4Gz2";
 
    public static String doGet(String url){
        BufferedReader reader = null;
        String bookHSONString = null;
        String bookJSONString;
        HttpURLConnection httpURLConnection = null;
        try{
            String uc = null;
            //1.HttpURLConnection建立连接
 
            URL requestUrl = new URL(url);
            httpURLConnection = (HttpURLConnection)requestUrl.openConnection();//打开连接
            httpURLConnection.setRequestMethod("GET");//两种方法GET/POST
            httpURLConnection.setConnectTimeout(5000);//设置超时连接时间
            httpURLConnection.connect();
 
            //2.InputStream获取二进制流
            InputStream inputstream = httpURLConnection.getInputStream();
 
            //3.InputStreamReader将二进制流进行包装成BufferedReader
            reader = new BufferedReader(new InputStreamReader(inputstream));
 
            //4.从BufferedReader中读取String字符串,用StringBulider接收
            StringBuilder builder = new StringBuilder();
 
 
            String line;
            while((line=reader.readLine())!=null){
                builder.append(line);
                builder.append("\n");
            }
 
            if(builder.length()==0)
            {
                return null;
            }
 
            //5.StringBulider将字符串进行拼接
            bookJSONString = builder.toString();
 
        }
 
        catch (ProtocolException e) {
            throw new RuntimeException(e);
        } catch (MalformedURLException e) {
            throw new RuntimeException(e);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
 
 
        finally {
            // 关闭连接
            if (httpURLConnection != null) {
                httpURLConnection.disconnect();
            }
            if (reader != null) {
                try {
                    reader.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        return bookJSONString;
    }
 
    public static String getWeatherOfCity(String city){
        //拼接处get请求的url
        String weatherUrl = BASE_URL+"?"+"appid="+APP_ID+"&"+"appsecret="+APP_SECRET+"&"+"city="+city;
        //打印上面的url
        Log.d("fan","-----weatherUrl----"+weatherUrl);
 
        //调用上文所写的doGet方法，传参
        String weatherResult = doGet(weatherUrl);
        return decodeUnicode(weatherResult);
    }
 
    //解码Unicode，将其转化为我们认识的汉字
    public static String decodeUnicode(String unicodeStr) {
        if (unicodeStr == null) {
            return null;
        }
        StringBuffer retBuf = new StringBuffer();
        int maxLoop = unicodeStr.length();
        for (int i = 0; i < maxLoop; i++) {
            if (unicodeStr.charAt(i) == '\\') {
                if ((i < maxLoop - 5) && ((unicodeStr.charAt(i + 1) == 'u') || (unicodeStr.charAt(i + 1) == 'U')))
                    try {
                        retBuf.append((char) Integer.parseInt(unicodeStr.substring(i + 2, i + 6), 16));
                        i += 5;
                    } catch (NumberFormatException localNumberFormatException) {
                        retBuf.append(unicodeStr.charAt(i));
                    }
                else
                    retBuf.append(unicodeStr.charAt(i));
            } else {
                retBuf.append(unicodeStr.charAt(i));
            }
        }
        return retBuf.toString();
    }
 
 
}
 
 
 
 

NetUtil.java   运行子线程