应用HttpURLConnection读取InputStream信息

EGGer — Thu, 30 Apr 2009 06:49:49 +0000

基于Android平台的应用开发大部分都会涉及到应用网络资源，然而通过指定的URL来读取数据可以算得上是最基本的应用。下面通过一个小例子演示如何实现这个方法。

注意：在调试代码之前，请首先确认AndroidManifest中已经添加了Internet permission标签。

源代码：


    private void getConnStream(){

    	String result = null;
    	URL url = null;
		try {
			url = new URL("http://www.androidres.com");
		} catch (MalformedURLException e) {
			Log.e("TestConnStream_URL",e.getMessage());
		}

		if (url != null) {
			try {
				HttpURLConnection urlConn = (HttpURLConnection) url
						.openConnection();
				BufferedReader in = new BufferedReader(new InputStreamReader(
						urlConn.getInputStream()));
				String inputLine;

				int lineCount = 0; // limit the lines for the example

		        while ((lineCount < 8 ) && ((inputLine = in.readLine()) != null)) {
		             lineCount++;
		             result += "\n" + inputLine;
		        }

		        in.close();
		        urlConn.disconnect();

			} catch (IOException e) {
				Log.e("TestConnStream",e.getMessage());
			}
		}
    }

返回的result结果：

Android Resource | Android 资源 - 资讯 - 教程 |

如何应用ImageView读取网络图片资源

Edgar Sun — Thu, 09 Apr 2009 10:03:09 +0000

这个教程将演示如何应用ImageView读取网络图片资源。有两个比较重要的知识点需要特别注意：

应用HttpURLConnection获得图片数据。
通过BitmapFactory将数据转换为可供ImageView识别的图像资源。

Layout 源代码（XML）：

主程序源代码（Java）：

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;

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;

public class HTTPTest extends Activity {

     ImageView imView;
     String imageUrl="http://11.0.6.23/";
     Random r;
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        setContentView(R.layout.main);
        r= new Random();

        Button bt3= (Button)findViewById(R.id.get_imagebt);
        bt3.setOnClickListener(getImgListener);
        imView = (ImageView)findViewById(R.id.imview);
    }    

    View.OnClickListener getImgListener = new View.OnClickListener()
    {

          @Override
          public void onClick(View view) {
               // TODO Auto-generated method stub

               //i tried to randomize the file download, in my server i put 4 files with name like
                        //png0.png, png1.png, png2.png so different file is downloaded in button press
               int i =r.nextInt()%4;
               downloadFile(imageUrl+"png"+i+".png");
               Log.i("im url",imageUrl+"png"+i+".png");
          }

    };

    Bitmap bmImg;
    void downloadFile(String fileUrl){
          URL myFileUrl =null;
          try {
               myFileUrl= new URL(fileUrl);
          } catch (MalformedURLException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
          }
          try {
               HttpURLConnection conn= (HttpURLConnection)myFileUrl.openConnection();
               conn.setDoInput(true);
               conn.connect();
               int length = conn.getContentLength();

               InputStream is = conn.getInputStream();

               bmImg = BitmapFactory.decodeStream(is);
               imView.setImageBitmap(bmImg);
          } catch (IOException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
          }
     }
}

Android Resource | 资源 资讯 教程 » HttpURLConnection

应用HttpURLConnection读取InputStream信息

Android Resource | Android 资源 - 资讯 - 教程 |

如何应用ImageView读取网络图片资源

Android Resource | 资源资讯教程 » HttpURLConnection