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package com.example.android_handler_message;import java.io.IOException;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.util.EntityUtils;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.app.Activity;import android.app.ProgressDialog;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.view.Menu;import android.view.View;import android.widget.Button;import android.widget.ImageView;public class MainActivity extends Activity { private static int IS_FINISHED = 1; private Button button = null; private ImageView p_w_picpathView = null; private String p_w_picpath_path = "http://i1.juyouqu.com/uploads/content//2014/04/1396611698344.jpg!w598"; private ProgressDialog dialog = null; private Handler handle = new Handler(){ public void handleMessage(android.os.Message msg) { Bitmap bitmap = null; byte[] data = (byte[])msg.obj; bitmap = BitmapFactory.decodeByteArray(data, 0, data.length); if(msg.what == IS_FINISHED) { dialog.dismiss(); p_w_picpathView.setImageBitmap(bitmap); } } }; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); button = (Button)findViewById(R.id.button1); p_w_picpathView = (ImageView)findViewById(R.id.p_w_picpathView1); dialog = new ProgressDialog(this); dialog.setTitle("提示"); dialog.setMessage("正在下载.........."); button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View arg0) { // TODO Auto-generated method stub new Thread(new MyTask()).start(); dialog.show(); } }); } public class MyTask implements Runnable { @Override public void run() { // TODO Auto-generated method stub HttpClient httpClient = new DefaultHttpClient(); HttpGet httpGet = new HttpGet(p_w_picpath_path); try { HttpResponse httpResponse = httpClient.execute(httpGet); if(httpResponse.getStatusLine().getStatusCode() == 200) { byte[] data = EntityUtils.toByteArray(httpResponse.getEntity()); Message message = Message.obtain(); message.obj = data; message.what = IS_FINISHED; handle.sendMessage(message); } } catch (ClientProtocolException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }}