Android异步任务AsyncTask

 package com.example.asynctask;

 import java.net.MalformedURLException;
 import java.net.URL;

 import android.app.Activity;
 import android.os.AsyncTask;
 import android.os.Bundle;
 import android.util.Log;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.widget.TextView;
 /**
  * 异步任务实现，可以实现直接修改UI线程的控件。
  * @author shb
  *
  */
 public class MainActivity extends Activity {
     private TextView tView;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         tView = (TextView) this.findViewById(R.id.textView1);
         TestAsyn testAsyn = new TestAsyn();
         try {
             testAsyn.execute(new URL("https://www.baidu.com/img/bd_logo1.png"));
         } catch (MalformedURLException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }
     }
     public class TestAsyn extends AsyncTask<URL,Integer,String> {

         @Override
         protected String doInBackground(URL... arg0) {
             // TODO Auto-generated method stub
             return arg0[0].toString();
         }
         @Override
         protected void onPostExecute(String result) {
             // TODO Auto-generated method stub
             super.onPostExecute(result);
             MainActivity.this.tView.setText(result);
         }
         @Override
         protected void onPreExecute() {
             // TODO Auto-generated method stub
             super.onPreExecute();
             Log.d("msg","onPreex");
         }
     }
 }