在AndroidManifest.xml里面先添加访问网络的权限：
<uses-permission android:name="android.permission.INTERNET"/>
效果图如下
：
下面是主要代码：
package com.hb.neting; import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL; import android.annotation.SuppressLint;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast; public class MainActivity extends Activity {
private ImageView iv_show;
private EditText et_input;
private String path;
private int code;
private HttpURLConnection conn;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
iv_show=(ImageView) findViewById(R.id.iv_show);
et_input=(EditText) findViewById(R.id.et_inpput);
}
@SuppressLint("ShowToast") public void chakan(View view){
path = et_input.getText().toString().trim();
if (TextUtils.isEmpty(path)) {
Toast.makeText(MainActivity.this, "不能输入空的", 0).show();
return;
}
new Thread(){
public void run() {
try {
URL url = new URL(path);
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(5000);
code = conn.getResponseCode();
if(code==200){
InputStream in = conn.getInputStream();
//解析图片
final Bitmap stream = BitmapFactory.decodeStream(in);
runOnUiThread(new Runnable() {
public void run() {
//更新UI
iv_show.setImageBitmap(stream);
}
});
in.close();
}
} catch (Exception e) {
e.printStackTrace();
}
};
}.start();
}
}
这是xml的布局：
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" > <EditText
android:id="@+id/et_inpput"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="请输入获取图片的地址：" />
<Button
android:id="@+id/bt_read"
android:onClick="chakan"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="查看"
/>
<ImageView
android:id="@+id/iv_show"
android:layout_width="match_parent"
android:layout_height="match_parent"
/>
</LinearLayout>
源码：http://pan.baidu.com/s/1bUgMgY
接着看一下网页源码查看器的小案例：
既然都涉及到网络的添加一个如上的网络权限是必不可少的了，具体操做如上所示，先看效果图：
主要代码：
package com.hb.network; import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL; import android.annotation.SuppressLint;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast; import com.hb.utils.ReadStreamUtils; public class MainActivity extends Activity {
protected static final int SUCESS = 0;
protected static final int EORR = 1;
private TextView tv_show;
private EditText et_input;
private URL url;
private String path;
@SuppressLint("HandlerLeak")
private Handler handler=new Handler(){
public void handleMessage(android.os.Message msg) {
switch (msg.what) {
case SUCESS:
String content=(String) msg.obj;
tv_show.setText(content);
break; case EORR:
Toast.makeText(MainActivity.this,"查看源码失败" , 0).show();
break;
}
};
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv_show=(TextView) findViewById(R.id.tv_show);
et_input=(EditText) findViewById(R.id.et_input); }
public void onclick(View view){
path = et_input.getText().toString().trim();
if(TextUtils.isEmpty(path)){
return;
}new Thread(){
public void run() {
try {
url = new URL(path);
//判断从EditText获取的数据否为空
if(TextUtils.isEmpty(path)){
return;
}
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(3000);
conn.setRequestMethod("GET");
int code = conn.getResponseCode();
if(code == 200){
InputStream is= conn.getInputStream();
String content = ReadStreamUtils.Read(is);
Message msg = new Message();
msg.what=SUCESS;
msg.obj=content;
handler.sendMessage(msg);
}
} catch (Exception e) {
e.printStackTrace();
Message msg = new Message();
msg.what=EORR;
handler.sendMessage(msg);
}
};
}.start(); }
}
package com.hb.utils; import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream; public class ReadStreamUtils {
/**
* 读取流的输入
* @param is
* @return
* @throws IOException
*/
public static String Read(InputStream is) throws IOException{
ByteArrayOutputStream bos = new ByteArrayOutputStream();
int len;
byte [] buffer=new byte[1024];
while((len=is.read(buffer))!=-1){
bos.write(buffer,0,len);
}
is.close();
bos.close();
String temp = bos.toString();
if(temp.contains("charset=utf-8")){
return bos.toString("utf-8");
}else if(temp.contains("charset=iso-8859-1")){
return bos.toString("iso-8859-1");
}
return null; } }
及xml布局:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" > <EditText
android:id="@+id/et_input"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="请输入要查看源码的网址：" /> <Button
android:onClick="onclick"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="查看"
android:textSize="25sp" /> <ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent" > <TextView
android:id="@+id/tv_show"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</ScrollView> </LinearLayout>
源码：http://pan.baidu.com/s/1bUgMgY
http://pan.baidu.com/s/1i46RQqL