【AsynTask】Android异步加载一张图品

package com.test.asyntask;



import java.io.IOException;

import java.io.InputStream;

import java.net.URL;

import android.app.Activity;

import android.app.ProgressDialog;

import android.graphics.drawable.Drawable;

import android.os.AsyncTask;

import android.os.Bundle;

import android.widget.ImageView;



import com.test.R;



public class AsynTask extends Activity {



    private ImageView mImage;

    private ProgressDialog mDialog;



    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.asyn_task);



        mDialog = new ProgressDialog(this);

        mDialog.setTitle("请稍等");

        mDialog.setMessage("正在加载...");



        mImage = (ImageView) findViewById(R.id.img);

        new ImageAsynTask().execute();

    }



    private class ImageAsynTask extends AsyncTask<Void, Void, Drawable> {

        @Override

        protected Drawable doInBackground(Void... params) {

            String url = "http://img1.3lian.com/img2011/07/20/05.jpg";

            return loadImages(url);

        }

        @Override

        protected void onPostExecute(Drawable result) {

            super.onPostExecute(result);

            mDialog.dismiss();

            mImage.setImageDrawable(result);

        }

        @Override

        protected void onPreExecute() {

            super.onPreExecute();

            mDialog.show();

        }

    }



    @Override

    protected void onDestroy() {

        super.onDestroy();

        mDialog.dismiss();

    }



    public Drawable loadImages(String url) {

        try {

            return Drawable.createFromStream(

                    (InputStream) (new URL(url)).openStream(), "test");

        } catch (IOException e) {

            e.printStackTrace();

        }

        return null;

    }

}

View Code