android - 一次调用多个 AsyncTask 在 Android 中不起作用

Question

我想调用多个AsynTask。它没有用，所以我用谷歌搜索寻求帮助。我发现如果我使用 AsyncTask.THREAD_POOL_EXECUTOR 那么它就会工作。

但它不起作用。

我这样调用它:

new GetCategory().execute();
new GetArea().executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);

请帮我解决这个问题。我想一次调用它，或者在 GetCategory() 之后调用 GetArea() 也可以。 我没有收到错误。应用程序可能正在做太多工作。
日志:

03-13 21:21:43.134: I/Choreographer(1222): Skipped 39 frames!  The application may be doing too much work on its main thread.
03-13 21:21:43.394: I/Choreographer(1222): Skipped 43 frames!  The application may be doing too much work on its main thread.
03-13 21:21:43.634: I/Choreographer(1222): Skipped 36 frames!  The application may be doing too much work on its main thread.
03-13 21:21:43.784: I/Choreographer(1222): Skipped 38 frames!  The application may be doing too much work on its main thread.
03-13 21:21:44.004: I/Choreographer(1222): Skipped 56 frames!  The application may be doing too much work on its main thread.
03-13 21:21:44.164: I/Choreographer(1222): Skipped 36 frames!  The application may be doing too much work on its main thread.
03-13 21:21:45.495: I/Choreographer(1222): Skipped 33 frames!  The application may be doing too much work on its main thread.
03-13 21:21:45.765: I/Choreographer(1222): Skipped 43 frames!  The application may be doing too much work on its main thread.
03-13 21:21:46.005: I/Choreographer(1222): Skipped 36 frames!  The application may be doing too much work on its main thread.
03-13 21:21:46.235: I/Choreographer(1222): Skipped 44 frames!  The application may be doing too much work on its main thread.
03-13 21:21:46.525: I/Choreographer(1222): Skipped 48 frames!  The application may be doing too much work on its main thread.
03-13 21:21:46.855: I/Choreographer(1222): Skipped 39 frames!  The application may be doing too much work on its main thread.
03-13 21:21:47.005: I/Choreographer(1222): Skipped 39 frames!  The application may be doing too much work on its main thread.
03-13 21:21:47.156: I/Choreographer(1222): Skipped 37 frames!  The application may be doing too much work on its main thread.
03-13 21:21:47.306: I/Choreographer(1222): Skipped 38 frames!  The application may be doing too much work on its main thread.

我在两个 AsynTask 上都绑定(bind)了 Spinner。
我的代码:

        Area[] areaList = gson.fromJson(result, Area[].class);

        List<Area> lList = Arrays.asList(areaList);
        Area objArea;

        areaId.add("0");
        areaName.add("Select Area");

        for (int i = 0; i < lList.size(); i++) {
            objArea = lList.get(i);
            areaName.add(objArea.getAreaName());
            areaId.add(objArea.getAreaId());
        }

        ArrayAdapter<String> adapter = new ArrayAdapter<String>(
                        getActivity(), android.R.layout.simple_dropdown_item_1line, areaName);
                ((Spinner) spnCEArea).setAdapter(adapter);

Answer 1

之所以不能在同一个项目中的AsyncTask上同时调用两个.execute()方法是因为Android自引入的修改> Gingerbread 。在此版本之前，您可以根据需要多次调用 .execute()，因为它们中的每一个都在单独的 Thread 中运行。

但是从这个版本开始，它们是按顺序调用的，所以如果一个正在执行，如果您只调用 .execute()，另一个将不会启动。

所以基本上您需要做的就是检查您正在运行 AsyncTask 的设备的版本，并根据它运行一个或其他命令。

if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.HONEYCOMB_MR1)
  your_asynctask.execute(your_params);
else
  your_asynctask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, your_params);

更多信息 here .

顺便说一句，The application may be doing too much work on its main thread. 行与 AsyncTask 无关。这些任务在后台运行，如果您在 doInBackground() 方法中完成这些工作，那不是问题。

如果您在 onPostExecute() 任务中做一些工作，情况可能会略有不同，因为这可能与您的主 UI 有关，但我们不能在不知道的情况下告诉您更多信息您正在运行的代码。