看来你可以从别的地方开始的AsyncTask比主线程,但postExecute是在主线程实际执行。 这里是我的测试,告诉我,如果它似乎是合乎逻辑您:
public class AsyncLoader extends AsyncTask<Context, String, Boolean> {
private ConnectivityManager cm;
private ArrayList<Contact> nameList;
private Context ctx;
private static int i = 0;
@Override
protected Boolean doInBackground(Context... params) {
ctx = params[0];
cm = (ConnectivityManager) params[0].getSystemService(Activity.CONNECTIVITY_SERVICE);
if (i < 3) {
i++;
new AsyncLoader().execute(ctx);
System.out.println("Thread name (from doInBackground) : " + Thread.currentThread().getName());
System.out.println("compteur async " + i);
}
if (cm.getActiveNetworkInfo() != null && cm.getActiveNetworkInfo().isAvailable()) {
nameList = (ArrayList<Contact>) ContactLoaderXml.loadContactsData(); //this is a loading from the web + sax parser
return true;
} else {
return false;
}
}
@Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
System.out.println("Thread name (from postexecute) : " + Thread.currentThread().getName());
}
}
这里是任务后的堆栈跟踪:
I/System.out( 641): Thread name (from doInBackground) : AsyncTask #1
I/System.out( 641): compteur async 1
I/System.out( 641): Thread name (from doInBackground) : AsyncTask #2
I/System.out( 641): compteur async 2
I/System.out( 641): Thread name (from doInBackground) : AsyncTask #3
I/System.out( 641): compteur async 3
I/System.out( 641): Thread name (from postexecute) : main
I/System.out( 641): Thread name (from postexecute) : main
I/System.out( 641): Thread name (from postexecute) : main
I/System.out( 641): Thread name (from postexecute) : main
我不知道为什么执行后完成4次虽然...
文档*对我来说似乎有误导性,但我没有跑过你得到的异常是我的经验,当在UI线程外部使用'AsyncTask'时,onPostExecute'发生在调用线程中,而不一定是UI线程(如果UI需要被操作,则需要'Handler')。 – 2010-07-21 16:07:30