package com.example.myroom.network;
import android.app.Activity;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
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.URL;
public class MainActivity extends Activity implements View.OnClickListener {
public static final int SHOW_RESPONSE=0; private Button sendRequest; private TextView responseText; StringBuilder response=new StringBuilder(); private Handler handler=new Handler(){ @Override public void handleMessage(Message msg) { switch (msg.what){ case SHOW_RESPONSE: String response=(String)msg.obj; responseText.setText(response); } super.handleMessage(msg); } }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); sendRequest=(Button)this.findViewById(R.id.send_request); responseText=(TextView)this.findViewById(R.id.response); sendRequest.setOnClickListener(this); } @Override public void onClick(View view) { if(view.getId()==R.id.send_request){ sendRequestWithHttpURLConnection(); responseText.setText(response); } } private void sendRequestWithHttpURLConnection() { new Thread(){ @Override public void run() { HttpURLConnection connection=null; try{ URL url=new URL("http://www.baidu.com"); connection=(HttpURLConnection)url.openConnection(); connection.setRequestMethod("GET"); connection.setConnectTimeout(8000); connection.setReadTimeout(8000); InputStream in=connection.getInputStream(); BufferedReader reader=new BufferedReader(new InputStreamReader(in)); String line; while((line=reader.readLine())!=null){ response.append(line); } Message message=new Message(); message.what=SHOW_RESPONSE; message.obj=response.toString(); handler.sendMessage(message); } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); }finally { if(connection!=null){ connection.disconnect(); } } super.run(); } }.start(); }
}
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
有加权限,但不显示
照你的代码,我试了下,可以的啊
import android.os.Bundle; import android.os.Handler; import android.os.Message; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.widget.Button; import android.widget.TextView; 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.URL; public class MainActivity extends AppCompatActivity implements View.OnClickListener { public static final int SHOW_RESPONSE = 0; private Button sendRequest; private TextView responseText; StringBuilder response = new StringBuilder(); private Handler handler = new Handler() { @Override public void handleMessage(Message msg) { switch (msg.what) { case SHOW_RESPONSE: String response = (String) msg.obj; responseText.setText(response); } super.handleMessage(msg); } }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); sendRequest = (Button) findViewById(R.id.send_request); sendRequest.setOnClickListener(this); responseText = (TextView) findViewById(R.id.response); } @Override public void onClick(View view) { if (view.getId() == R.id.send_request) { sendRequestWithHttpURLConnection(); responseText.setText(response); } } private void sendRequestWithHttpURLConnection() { new Thread() { @Override public void run() { HttpURLConnection connection = null; try { URL url = new URL("https://m.baidu.com/#"); connection = (HttpURLConnection) url.openConnection(); connection.setRequestMethod("GET"); connection.setConnectTimeout(8000); connection.setReadTimeout(8000); InputStream in = connection.getInputStream(); BufferedReader reader = new BufferedReader(new InputStreamReader(in)); String line; while ((line = reader.readLine()) != null) { response.append(line); } Message message = new Message(); message.what = SHOW_RESPONSE; message.obj = response.toString(); handler.sendMessage(message); } catch (MalformedURLException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { if (connection != null) { connection.disconnect(); } } super.run(); } }.start(); } }
<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/activity_main" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical"> <Button android:id="@+id/send_request" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="Send request"/> <ScrollView android:layout_width="match_parent" android:layout_height="match_parent" android:scrollbars="vertical"> <TextView android:id="@+id/response" android:layout_width="match_parent" android:layout_height="wrap_content"/> </ScrollView> </LinearLayout>
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
再检查一下网络权限吧
难道你没点按钮,或者模拟器没联网
照第一行代码抄写的?