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);

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";

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();
}

试试这个:

public class SomAsyncTask extends AsyncTask<String, Integer, JSONObject> {

    private CallBack callBack;

    public interface CallBack {
        void async( JSONObject jsonResult );
        void sync( JSONObject jsonResult );
        void progress( Integer... status );
        void cancel();
    }

    public SomAsyncTask(CallBack callBack) {
        this.callBack = callBack;
    }

    @Override
    protected JSONObject doInBackground(String... strings) {

        JSONObject dataJson = null;

        //TODO query, get some dataJson

        if(this.callBack != null)
            this.callBack.async( dataJson );// asynchronize with MAIN LOOP THREAD

        return dataJson;

    }

    @Override
    protected void onProgressUpdate(Integer... values) {
        super.onProgressUpdate(values);

        if(this.callBack != null)
            this.callBack.progress(values);// synchronize with MAIN LOOP THREAD

    }

    @Override
    protected void onPostExecute(JSONObject jsonObject) {
        super.onPostExecute(jsonObject);

        if(this.callBack != null)
            this.callBack.sync(jsonObject);// synchronize with MAIN LOOP THREAD
    }

    @Override
    protected void onCancelled() {
        super.onCancelled();

        if(this.callBack != null)
            this.callBack.cancel();

    }
}

用法示例:

public void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);

         final Context _localContext = getContext();
         SomeAsyncTask.CallBack someCallBack = new SomeAsyncTask.CallBack() {

                @Override
                public void async(JSONObject jsonResult) {//async thread
                    //some async process, e.g. send data to server...
                }

                @Override
                public void sync(JSONObject jsonResult) {//sync thread
                    //get result...

                    //get some resource of Activity variable...
                    Resources resources = _localContext.getResources();
                }

                @Override
                public void progress(Integer... status) {//sync thread
                    //e.g. change status progress bar...
                }

                @Override
                public void cancel() {

                }

            };

            new SomeAsyncTask( someCallBack )
                                .execute("someParams0", "someParams1", "someParams2");

    }

希望你已经读过了，如果没有，请阅读。

https://developer.android.com/reference/android/os/AsyncTask

根据结果数据的性质，您应该选择您能想到的最佳选项。

使用接口是一个很好的选择

其他的选择是…

If the AsyncTask class is defined inside the very class you want to use the result in.Use a static global variable or get() , use it from outer class (volatile variable if necessary). but should be aware of the AsyncTask progress or should at least make sure that it have finished the task and result is available through global variable / get() method. you may use polling, onProgressUpdate(Progress...), synchronization or interfaces (Which ever suits best for you) If the Result is compatible to be a sharedPreference entry or it is okay to be saved as a file in the memory you could save it even from the background task itself and could use the onPostExecute() method to get notified when the result is available in the memory. If the string is small enough, and is to be used with start of an activity. it is possible to use intents (putExtra()) within onPostExecute() , but remember that static contexts aren't that safe to deal with. If possible, you can call a static method from the onPostExecute() method, with the result being your parameter

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");

}


}