异步加载图片

package com.example.asynctask;

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

import org.apache.http.HttpEntity;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.DefaultClientConnection;
import org.apache.http.util.EntityUtils;

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.AsyncTaskLoader;
import android.content.Entity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends Activity {
Button button;
ImageView img;
ProgressDialog prodialog;
private String imagpath="http://c.hiphotos.baidu.com/album/w%3D2048/sign=483d6850f3d3572c66e29bdcbe2b6127/8644ebf81a4c510f9b15dda36159252dd52aa5b1.jpg";
//private String imagpath="http://pic1.win4000.com/wallpaper/5/5034895771d66.jpg";	
@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		button=(Button) findViewById(R.id.button1);
		img=(ImageView) findViewById(R.id.imageView1);	
		prodialog=new ProgressDialog(this);
		prodialog.setTitle("提示信息：");
		prodialog.setMessage("正在下载,请稍等......");
		prodialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
		button.setOnClickListener( new View.OnClickListener(){

			@Override
			public void onClick(View v) {
				new Mytask().execute(imagpath);
				
			}
			
			
		});
	}
	/*
	 * 
	 * 
	 * */

	/*public class Mytask extends AsyncTask<String, Void, Bitmap>{

		 Bitmap bitmap;
		
		@Override
		protected void onPreExecute() {
			// TODO Auto-generated method stub
			super.onPreExecute();
			prodialog.show();
		}

		@Override
		protected Bitmap doInBackground(String... params) {
			HttpClient httpClient=new  DefaultHttpClient();
			HttpGet httpGet=new HttpGet(params[0]);
			try {
				HttpResponse httpResponse=httpClient.execute(httpGet);
				if(httpResponse.getStatusLine().getStatusCode()==200){
					HttpEntity entity=httpResponse.getEntity();
					byte[] data=EntityUtils.toByteArray(entity);
					 bitmap=BitmapFactory.decodeByteArray(data, 0, data.length);
					
				}
			} catch (ClientProtocolException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			return bitmap;
		}
		@Override
		protected void onPostExecute(Bitmap result) {
			// TODO Auto-generated method stub
			super.onPostExecute(result);
			prodialog.dismiss();
			img.setImageBitmap(bitmap);
		}
	
	}*/
	public class Mytask extends AsyncTask<String, Integer, Bitmap>{
Bitmap bitmap;
		@Override
		protected Bitmap doInBackground(String... params) {
			// TODO Auto-generated method stub
   ByteArrayOutputStream outputStream=new ByteArrayOutputStream();
   InputStream inputStream=null;
			HttpClient httpClient=new  DefaultHttpClient();
			HttpGet httpGet=new HttpGet(params[0]);
			
			
			try {
				HttpResponse httpResponse=httpClient.execute(httpGet);
				if(httpResponse.getStatusLine().getStatusCode()==200){
				inputStream=httpResponse.getEntity().getContent();
				long file_length=httpResponse.getEntity().getContentLength();
			int len=0;
		 long total_length=0;
			byte[] data=new byte[1024];
			while((len=inputStream.read(data))!=-1){
				System.out.println("a "+len+"---"+file_length);
				total_length+=len;
				System.out.println("total_length "+total_length);

				outputStream.write(data, 0, len);
				int values=(int) ((total_length/(float)file_length)*100);
				publishProgress(values);
				System.out.println("p  "+values);
			}byte[] result=outputStream.toByteArray();
			 bitmap=BitmapFactory.decodeByteArray(result, 0, result.length);
				}
				}catch(Exception e){
		e.printStackTrace();
				}finally{
					if(inputStream!=null)
						try {
							inputStream.close();
						} catch (IOException e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						}
				}
						return bitmap;	
		}

		@Override
		protected void onPostExecute(Bitmap result) {
			// TODO Auto-generated method stub
			super.onPostExecute(result);
			prodialog.dismiss();
			img.setImageBitmap(result);
		}

		@Override
		protected void onPreExecute() {
			// TODO Auto-generated method stub
			super.onPreExecute();
			prodialog.show();
		}

		@Override
		protected void onProgressUpdate(Integer... values) {
			// TODO Auto-generated method stub
			super.onProgressUpdate(values);
	
			prodialog.setProgress(values[0]);
		}
		
	}
	
	
	
	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.main, menu);
		return true;
	}

}

异步加载图片,布布扣,bubuko.com

异步加载图片

原文：http://blog.csdn.net/fangchao3652/article/details/20914535