Android AsyncTask 详解

核心提示：ImageView imageView01;TextView textView;@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.mai

ImageView imageView01;

TextView textView;

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

textView = (TextView) this.findViewById(R.id.TextView01);

imageView01 = (ImageView) this.findViewById(R.id.ImageView01);

GetImage getImage = new GetImage();

getImage.execute("http://hi.csdn.net/attachment/201010/27/0_1288149117Yk8W.gif");

}

private class GetImage extends AsyncTask {

public GetImage() {

super();

// TODO Auto-generated constructor stub

}

@Override

protected void onCancelled() {

Log.i("czb", "onCancelled is running...");

super.onCancelled();

}

@Override

protected void onPostExecute(Object result) {

/*

* 此方法在主线程执行，任务执行的结果作为此方法的参数返回

*/

Log.i("czb", "onPostExecute is running...");

Log.i("czb", "result == null ? " + (result == null));

imageView01.setImageBitmap((Bitmap)result);

super.onPostExecute(result);

}

@Override

protected void onPreExecute() {

/*

* 执行预处理，它运行于UI线程，可以为后台任务做一些准备工作，比如绘制一个进度条控件

*/

Log.i("czb", "onPreExecute is running...");

super.onPreExecute();

}

@Override

protected void onProgressUpdate(Object... values) {

/*

* 此方法在主线程执行，用于显示任务执行的进度。

*/

Log.i("czb", "onProgressUpdate is running...");

// 由publishProgress传递的值

Log.i("czb", "values " + values[0]);

super.onProgressUpdate(values);

}

@Override

protected Object doInBackground(Object... params) {