Android開發（13）-- 互聯網訪問圖片，在android客戶端顯示

1、布局界面
[html]
<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>
[html]
<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> 

<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：

[java]
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;
}
}
[java]
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; 
    } 
} 

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

[java]
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;
}
}
[java]
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; 
    } 
} 

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

[java]
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;
}
}
[java]
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; 
    } 
} 

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

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

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