在Oncreate()中:

`

myTask.execute("url");
String result = "";
try {
      result = myTask.get().toString();
} catch (InterruptedException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
}catch (ExecutionException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();

}`

在Activity类中创建一个静态成员。然后在onPostExecute期间分配该值

例如，如果你的AsyncTask的结果是一个字符串，在你的Activity中创建一个公共静态字符串

datfromasynctask;

然后，在AsyncTask的onPostExecute中，简单地对主类进行静态调用并设置值。

MainActivity。dataFromAsyncTask = "result blah";

为什么人们把事情搞得这么难。

这应该足够了。

不要在异步任务上实现onPostExecute，而是在Activity上实现它:

public class MainActivity extends Activity 
{

@Override
public void onCreate(Bundle savedInstanceState) {

    //execute the async task 
    MyAsyncTask task = new MyAsyncTask(){
            protected void onPostExecute(String result) {
                //Do your thing
            }       

    }

    task.execute("Param");

}


}

嗨，你可以做这样的东西:

Create class which implements AsyncTask // TASK public class SomeClass extends AsyncTask<Void, Void, String>> { private OnTaskExecutionFinished _task_finished_event; public interface OnTaskExecutionFinished { public void OnTaskFihishedEvent(String Reslut); } public void setOnTaskFinishedEvent(OnTaskExecutionFinished _event) { if(_event != null) { this._task_finished_event = _event; } } @Override protected void onPreExecute() { super.onPreExecute(); } @Override protected String doInBackground(Void... params) { // do your background task here ... return "Done!"; } @Override protected void onPostExecute(String result) { super.onPostExecute(result); if(this._task_finished_event != null) { this._task_finished_event.OnTaskFihishedEvent(result); } else { Log.d("SomeClass", "task_finished even is null"); } } } Add in Main Activity // MAIN ACTIVITY public class MyActivity extends ListActivity { ... SomeClass _some_class = new SomeClass(); _someclass.setOnTaskFinishedEvent(new _some_class.OnTaskExecutionFinished() { @Override public void OnTaskFihishedEvent(String result) { Toast.makeText(getApplicationContext(), "Phony thread finished: " + result, Toast.LENGTH_SHORT).show(); } }); _some_class.execute(); ... }

我通过使用线程和处理程序/消息使它工作。 步骤如下: 声明进度对话框

ProgressDialog loadingdialog;

创建一个函数，在操作结束时关闭对话框。

   private Handler handler = new Handler() {
    @Override
    public void handleMessage(Message msg) {
        loadingdialog.dismiss();

    }
    };

编码你的执行细节:

 public void startUpload(String filepath) {
    loadingdialog = ProgressDialog.show(MainActivity.this, "Uploading", "Uploading Please Wait", true);
    final String _path = filepath;
    new Thread() {
        public void run() {
            try {
                UploadFile(_path, getHostName(), getPortNo());
                handler.sendEmptyMessage(0);

            } catch (Exception e) {
                Log.e("threadmessage", e.getMessage());
            }
        }
    }.start();
}

可能有点过分了，但我为执行代码和结果都提供了回调。显然，为了线程安全，你要小心你在执行回调中访问的内容。

AsyncTask实现:

public class AsyncDbCall<ExecuteType,ResultType> extends AsyncTask<ExecuteType, Void,  
ResultType>
{
    public interface ExecuteCallback<E, R>
    {
        public R execute(E executeInput);
    }
    public interface PostExecuteCallback<R>
    {
        public void finish(R result);
    }

    private PostExecuteCallback<ResultType> _resultCallback = null;
    private ExecuteCallback<ExecuteType,ResultType> _executeCallback = null;


    AsyncDbCall(ExecuteCallback<ExecuteType,ResultType> executeCallback, PostExecuteCallback<ResultType> postExecuteCallback)
    {
        _resultCallback = postExecuteCallback;
        _executeCallback = executeCallback;
    }

    AsyncDbCall(ExecuteCallback<ExecuteType,ResultType> executeCallback)
    {
        _executeCallback = executeCallback;
    }

    @Override
    protected ResultType doInBackground(final ExecuteType... params)
    {
        return  _executeCallback.execute(params[0]);
    }

    @Override
    protected void onPostExecute(ResultType result)
    {
        if(_resultCallback != null)
            _resultCallback.finish(result);
    }
}

一个回调:

 AsyncDbCall.ExecuteCallback<Device, Device> updateDeviceCallback = new 
 AsyncDbCall.ExecuteCallback<Device, Device>()
    {
        @Override
        public Device execute(Device device)
        {
            deviceDao.updateDevice(device);
            return device;
        }
    };

最后执行异步任务:

 new AsyncDbCall<>(addDeviceCallback, resultCallback).execute(device);