image.png
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<Button
android:id="@+id/send_request"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="发送请求"
/>
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:id="@+id/response_text"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</ScrollView>
</LinearLayout>
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.networktest">
<uses-permission android:name="android.permission.INTERNET"/>
<application
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">
<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>
package com.example.networktest;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private static final String TAG = "MainActivity";
TextView responseText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button sendRequest = (Button) findViewById(R.id.send_request);
responseText = (TextView) findViewById(R.id.response_text);
sendRequest.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if (v.getId() == R.id.send_request) {
sendRequestWithHttpConnection();
}
}
private void sendRequestWithHttpConnection() {
//开启线程
new Thread(new Runnable() {
@Override
public void run() {
HttpURLConnection connection = null;
BufferedReader br = null;
try {
URL url = new URL("https://www.baidu.com/");
connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.setConnectTimeout(8000);
connection.setConnectTimeout(8000);
InputStream in = connection.getInputStream();
// 下面对输入流进行读取
br = new BufferedReader(new InputStreamReader(in));
StringBuilder response = new StringBuilder();
String line;
while((line=br.readLine())!=null){
response.append(line);
}
Log.d(TAG, "run: "+response.toString());
showResponse(response.toString());
} catch (Exception e) {
}
}
}).start();
}
private void showResponse(final String response) {
Log.d(TAG, "showResponse: "+response);
runOnUiThread(new Runnable() {
@Override
public void run() {
//进行ui操作 把结果显示到界面
responseText.setText(response);
}
});
}
}
通常建议使用handler进行处理:
package com.example.networktest;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private static final String TAG = "MainActivity";
TextView responseText;
//在主线程中定义一个handler
private Handler handler = new Handler(){
//这个方法是在主线程里面执行的
@Override
public void handleMessage(Message msg) {
//所以可以在主线程更新ui了
String str = (String) msg.obj;
//进行ui操作 把结果显示到界面
responseText.setText(response);
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button sendRequest = (Button) findViewById(R.id.send_request);
responseText = (TextView) findViewById(R.id.response_text);
sendRequest.setOnClickListener(this);
}
@Override
public void onClick(View v) {
if (v.getId() == R.id.send_request) {
sendRequestWithHttpConnection();
}
}
private void sendRequestWithHttpConnection() {
//开启线程
new Thread(new Runnable() {
@Override
public void run() {
HttpURLConnection connection = null;
BufferedReader br = null;
try {
URL url = new URL("https://www.baidu.com/");
connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.setConnectTimeout(8000);
connection.setConnectTimeout(8000);
//获取服务器返回的状态码
int code = conn.getResponseCode();
//如果code==200说明请求成功
if (code == 200) {
InputStream in = connection.getInputStream();
// 下面对输入流进行读取
br = new BufferedReader(new InputStreamReader(in));
StringBuilder response = new StringBuilder();
String line;
while((line=br.readLine())!=null){
response.append(line);
}
Log.d(TAG, "run: "+response.toString());
//获取成功 则返回服务器的返回数据 以流的形式返回的
//创建message对象
Message msg = new Message();
msg.obj =response.toString();
//拿我们的handler(助手)告诉系统我们要更新ui
handler.sendMessage(msg);
//把流的数据展示到textView上
//由于把流转字符串是常见操作 所以建议抽出来作为一个工具类utils
// tv_result.setText(str);
}
showResponse();
} catch (Exception e) {
}
}
}).start();
}
}