Android互聯網訪問圖片並在客戶端顯示的方法

本文實例講述了Android互聯網訪問圖片並在客戶端顯示的方法。分享給大家供大家參考，具體如下：

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、封轉的一些類

URL的封裝：

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{
   //設置訪問的url
   URL url=new URL(path);
   //打開請求
   HttpURLConnection httpURLConnection=(HttpURLConnection) url.openConnection();
   //設置請求的信息
   httpURLConnection.setRequestMethod("GET");
   //設置請求是否超時
   httpURLConnection.setConnectTimeout(5000);
   //判斷服務器是否響應成功
   if(httpURLConnection.getResponseCode()==200){
    //獲取響應的輸入流對象
    InputStream is=httpURLConnection.getInputStream();
    byte data[]=StreamTools.isTodata(is);
    //把轉換成字符串
    content=new String(data);
    //內容編碼方式
    if(content.contains("gb2312")){
     content=new String(data,"gb2312");
    }
   }
   //斷開連接
   httpURLConnection.disconnect();
  }catch(Exception e){
   e.printStackTrace();
  }
  return content;
 }
 public static Bitmap sendGets(String path){
  Bitmap bitmap=null;
  try{
   //設置訪問的url
   URL url=new URL(path);
   //打開請求
   HttpURLConnection httpURLConnection=(HttpURLConnection) url.openConnection();
   //設置請求的信息
   httpURLConnection.setRequestMethod("GET");
   //設置請求是否超時
   httpURLConnection.setConnectTimeout(5000);
   //判斷服務器是否響應成功
   if(httpURLConnection.getResponseCode()==200){
    //獲取響應的輸入流對象
    InputStream is=httpURLConnection.getInputStream();
    //直接把is的流轉換成Bitmap對象
    bitmap=BitmapFactory.decodeStream(is);
   }
   //斷開連接
   httpURLConnection.disconnect();
  }catch(Exception e){
   e.printStackTrace();
  }
  return bitmap;
 }
}

判斷網絡是否連接的封裝類

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;
 // 網路鏈接管理對象
 public ConnectivityManager connectivityManager;
 public NetWorkUtils(Context context) {
  this.context = context;
  // 獲取網絡鏈接的對象
  connectivityManager = (ConnectivityManager) context
    .getSystemService(Context.CONNECTIVITY_SERVICE);
 }
 public boolean setActiveNetWork() {
  boolean flag=false;
  // 獲取可用的網絡鏈接對象
  NetworkInfo networkInfo = connectivityManager.getActiveNetworkInfo();
  if (networkInfo == null) {
   new AlertDialog.Builder(context)
     .setTitle("網絡不可用")
     .setMessage("可以設置網絡?")
     .setPositiveButton("確認",
       new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog,
          int which) {
         Toast.makeText(context, "點擊確認",
           Toast.LENGTH_LONG).show();
         // 聲明意圖
         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);
         // 執行意圖
         context.startActivity(intent);
        }
       })
     .setNegativeButton("取消",
       new DialogInterface.OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog,
          int which) {
        }
       }).show();// 必須.show();
  }
  if(networkInfo!=null){
   flag=true;
  }
  return flag;
 }
}

輸出流的封裝類

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{
  //字節輸出流
  ByteArrayOutputStream bops=new ByteArrayOutputStream();
  //讀取數據的緩沖區
  byte buffer[]=new byte[1024];
  //讀取記錄的長度
  int len=0;
  while((len=is.read(buffer))!=-1){
   bops.write(buffer, 0, len);
  }
  //把讀取的內容轉換成byte數組
  byte data[]=bops.toByteArray();
  return data;
 }
}

注意：在這裡還需要加權限問題

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

希望本文所述對大家Android程序設計有所幫助。