Android从网络取得一张图片

从网络获得一张图片
1：StreamTool
package cn.itcast.utils;


import java.io.ByteArrayOutputStream;
import java.io.InputStream;


public class StreamTool {


/**
* 从输入流中获取数据
* @param inStream 输入流
* @return
* @throws Exception
*/
public static byte[] readInputStream(InputStream inStream) throws Exception{
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = 0;
while( (len=inStream.read(buffer)) != -1 ){
outStream.write(buffer, 0, len);
}
inStream.close();
return outStream.toByteArray();
}
}
 2：ImageService
package cn.itcast.service;


import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;


import cn.itcast.utils.StreamTool;


public class ImageService {

public static byte[] getImage(String path) throws Exception {
URL url = new URL("http://i3.itc.cn/20100707/76c_0969b700_d5b4_41cd_8243_9b486be92cc4_0.jpg");
HttpURLConnection conn = (HttpURLConnection)url.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(5 * 1000);
InputStream inStream = conn.getInputStream();//通过输入流获取图片数据
return StreamTool.readInputStream(inStream);//得到图片的二进制数据
}


}
 3：ImageShowActivity
package cn.itcast.image;


import cn.itcast.service.ImageService;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;


public class ImageShowActivity extends Activity {
private static final String TAG = "ImageShowActivity";
    private EditText pathText;
    private ImageView imageView;
    
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        pathText = (EditText) this.findViewById(R.id.urlpath);
        imageView = (ImageView) this.findViewById(R.id.imageView);
        Button button = (Button)this.findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String path = pathText.getText().toString();
try {
byte[] data = ImageService.getImage(path);
Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);//生成位图
imageView.setImageBitmap(bitmap);//显示图片
} catch (Exception e) {
Toast.makeText(ImageShowActivity.this, R.string.error, 1).show();
Log.e(TAG, e.toString());
}
}
});
    }
}
  4：
  <?xml version="1.0" encoding="utf-8" ?> 
- <manifest xmlns:android="http://schemas.android.com/apk/res/android" package="cn.itcast.image" android:versionCode="1" android:versionName="1.0">
- <application android:icon="@drawable/icon" android:label="@string/app_name">
- <activity android:name=".ImageShowActivity" android:label="@string/app_name">
- <intent-filter>
  <action android:name="android.intent.action.MAIN" /> 
  <category android:name="android.intent.category.LAUNCHER" /> 
  </intent-filter>
  </activity>
  </application>
  <uses-sdk android:minSdkVersion="8" /> 
- <!--  访问网络的权限 
  --> 
  <uses-permission android:name="android.permission.INTERNET" /> 
  </manifest>