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();

}`

容易:

Create interface class, where String output is optional, or can be whatever variables you want to return. public interface AsyncResponse { void processFinish(String output); } Go to your AsyncTask class, and declare interface AsyncResponse as a field : public class MyAsyncTask extends AsyncTask<Void, Void, String> { public AsyncResponse delegate = null; @Override protected void onPostExecute(String result) { delegate.processFinish(result); } } In your main Activity you need to implements interface AsyncResponse. public class MainActivity implements AsyncResponse{ MyAsyncTask asyncTask =new MyAsyncTask(); @Override public void onCreate(Bundle savedInstanceState) { //this to set delegate/listener back to this class asyncTask.delegate = this; //execute the async task asyncTask.execute(); } //this override the implemented method from asyncTask @Override void processFinish(String output){ //Here you will receive the result fired from async class //of onPostExecute(result) method. } }

更新

我不知道这是你们很多人的最爱。这是一个简单方便的界面使用方法。

仍然使用相同的界面。供参考，你可以把它合并到AsyncTask类中。

在AsyncTask类中:

public class MyAsyncTask extends AsyncTask<Void, Void, String> {

  // you may separate this or combined to caller class.
  public interface AsyncResponse {
        void processFinish(String output);
  }

  public AsyncResponse delegate = null;

    public MyAsyncTask(AsyncResponse delegate){
        this.delegate = delegate;
    }

    @Override
    protected void onPostExecute(String result) {
      delegate.processFinish(result);
    }
}

在你的活动课上做这个吗

public class MainActivity extends Activity {
  
   MyAsyncTask asyncTask = new MyAsyncTask(new AsyncResponse(){
    
     @Override
     void processFinish(String output){
     //Here you will receive the result fired from async class 
     //of onPostExecute(result) method.
     }
  }).execute();

 }

或者，再次在Activity上实现接口

public class MainActivity extends Activity 
    implements AsyncResponse{
      
    @Override
    public void onCreate(Bundle savedInstanceState) {

        //execute the async task 
        new MyAsyncTask(this).execute();
    }
      
    //this override the implemented method from AsyncResponse
    @Override
    void processFinish(String output){
        //Here you will receive the result fired from async class 
        //of onPostExecute(result) method.
    }
}

正如你可以看到上面的两个解决方案，第一个和第三个，它需要创建方法processFinish，另一个，方法在调用者参数中。第三种方法更加简洁，因为没有嵌套的匿名类。

提示:将String输出、String响应和String结果更改为不同的匹配类型，以便获得不同的对象。

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);

你可以调用AsyncTask的get()方法(或者重载的get(long, TimeUnit))。此方法将阻塞，直到AsyncTask完成它的工作，此时它将返回Result。

在创建/启动异步任务和调用get方法之间做其他工作是明智的，否则你不能非常有效地利用异步任务。

您可以在Main类中尝试此代码。 这对我来说很有效，但我已经用其他方式实现了方法

try {
    String receivedData = new AsyncTask().execute("http://yourdomain.com/yourscript.php").get();
} 
catch (ExecutionException | InterruptedException ei) {
    ei.printStackTrace();
}

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");

    }