Android互联网访问图片并在客户端显示的方法

本文实例讲述了Android互联网访问图片并在客户端显示的方法。分享给大家供大家参考，具体如下：

1、布局界面

<RelativeLayout 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:paddingBottom="@dimen/activity_vertical_margin"
 android:paddingLeft="@dimen/activity_horizontal_margin"
 android:paddingRight="@dimen/activity_horizontal_margin"
 android:paddingTop="@dimen/activity_vertical_margin"
 tools:context=".MainActivity" >
 <EditText
  android:id="@+id/url_text"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_alignParentLeft="true"
  android:layout_alignParentRight="true"
  android:layout_alignParentTop="true"
  android:ems="10"
  android:inputType="textPostalAddress"
  android:text="@string/url_text" >
  <requestFocus />
 </EditText>
 <Button
  android:id="@+id/btn_text"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_alignLeft="@+id/url_text"
  android:layout_below="@+id/url_text"
  android:layout_marginTop="32dp"
  android:onClick="sendHttp"
  android:text="@string/btn_text" />
 <ImageView
  android:id="@+id/iv_ie"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content"
  android:layout_alignParentBottom="true"
  android:layout_alignParentLeft="true"
  android:layout_alignRight="@+id/url_text"
  android:layout_below="@+id/btn_text"
  android:src="@drawable/ic_launcher" />
</RelativeLayout>

2、封转的一些类

URL的封装：

package com.example.lession08_code.utis;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
public class HttpUtils {
 public static String sendGet(String path){
  String content=null;
  try{
   //设置访问的url
   URL url=new URL(path);
   //打开请求
   HttpURLConnection httpURLConnection=(HttpURLConnection) url.openConnection();
   //设置请求的信息
   httpURLConnection.setRequestMethod("GET");
   //设置请求是否超时
   httpURLConnection.setConnectTimeout(5000);
   //判断服务器是否响应成功
   if(httpURLConnection.getResponseCode()==200){
    //获取响应的输入流对象
    InputStream is=httpURLConnection.getInputStream();
    byte data[]=StreamTools.isTodata(is);
    //把转换成字符串
    content=new String(data);
    //内容编码方式
    if(content.contains("gb2312")){
     content=new String(data,"gb2312");
    }
   }
   //断开连接
   httpURLConnection.disconnect();
  }catch(Exception e){
   e.printStackTrace();
  }
  return content;
 }
 public static Bitmap sendGets(String path){
  Bitmap bitmap=null;
  try{
   //设置访问的url
   URL url=new URL(path);
   //打开请求
   HttpURLConnection httpURLConnection=(HttpURLConnection) url.openConnection();
   //设置请求的信息
   httpURLConnection.setRequestMethod("GET");
   //设置请求是否超时
   httpURLConnection.setConnectTimeout(5000);
   //判断服务器是否响应成功
   if(httpURLConnection.getResponseCode()==200){
    //获取响应的输入流对象
    InputStream is=httpURLConnection.getInputStream();
    //直接把is的流转换成Bitmap对象
    bitmap=BitmapFactory.decodeStream(is);
   }
   //断开连接
   httpURLConnection.disconnect();
  }catch(Exception e){
   e.printStackTrace();
  }
  return bitmap;
 }
}

判断网络是否连接的封装类

package com.example.lession08_code.utis;
import android.app.AlertDialog;
import android.content.ComponentName;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.widget.Toast;
public class NetWorkUtils {
 private Context context;
 // 网路链接管理对象
 public ConnectivityManager connectivityManager;
 public NetWorkUtils(Context context) {
  this.context = context;
  // 获取网络链接的对象
  connectivityManager = (ConnectivityManager) context
    .getSystemService(Context.CONNECTIVITY_SERVICE);
 }
 public boolean setActiveNetWork() {
  boolean flag=false;
  // 获取可用的网络链接对象
  NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
  if (networkInfo == null) {
   new AlertDialog.Builder(context)
     .setTitle("网络不可用")
     .setMessage("可以设置网络?")
     .setPositiveButton("确认",
       new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog,
          int which) {
         Toast.makeText(context, "点击确认",
           Toast.LENGTH_LONG).show();
         // 声明意图
         Intent intent = new Intent();
         intent.setAction(Intent.ACTION_MAIN);
         intent.addCategory("android.intent.category.LAUNCHER");
         intent.setComponent(new ComponentName(
           "com.android.settings",
           "com.android.settings.Settings"));
         intent.setFlags(0x10200000);
         // 执行意图
         context.startActivity(intent);
        }
       })
     .setNegativeButton("取消",
       new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog,
          int which) {
        }
       }).show();// 必须.show();
  }
  if(networkInfo!=null){
   flag=true;
  }
  return flag;
 }
}

输出流的封装类

package com.example.lession08_code.utis;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
public class StreamTools {
 public static byte[] isTodata(InputStream is) throws IOException{
  //字节输出流
  ByteArrayOutputStream bops=new ByteArrayOutputStream();
  //读取数据的缓冲区
  byte buffer[]=new byte[1024];
  //读取记录的长度
  int len=0;
  while((len=is.read(buffer))!=-1){
   bops.write(buffer, 0, len);
  }
  //把读取的内容转换成byte数组
  byte data[]=bops.toByteArray();
  return data;
 }
}

注意：在这里还需要加权限问题

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
<uses-permission android:name="android.permission.INTERNET"/>

希望本文所述对大家Android程序设计有所帮助。