ScheduledThreadPoolExecutor用于定期任务（使用翻新），仅触发一次，不再触发

Question

我有以下代码用于每隔X秒从服务器轮询未读通知计数

我通过App.onCreate（）中的ScheduledThreadPoolExecutor启动此过程，然后

Log.d("XXX", "Requesting Notification count from server ...");

一次被调用（我在Logcat中可以看到），但是两个Retrofit回调函数都没有被调用（实际上没有Retrofit调试日志）。此外，永远不会再次打印“正在从服务器请求通知计数...。”（即，定期任务未运行）

我也将Retrofit用于其他Web服务调用（根据用户输入），并且它们工作正常（我可以在logcat中看到传入和传出的请求/响应）

public class App extends Application  {



    private ScheduledExecutorService scheduleTaskExecutor;
    ...


    @Override
    public void onCreate() {
        super.onCreate();

        //region Set up the periodic notification count listener task


        scheduleTaskExecutor= Executors.newScheduledThreadPool(2);
        scheduleTaskExecutor.scheduleAtFixedRate(new PeriodicNotifCountFetchTask(), 0, 5, TimeUnit.SECONDS);

        //endregion
    }


    class PeriodicNotifCountFetchTask implements Runnable {

        @Override
        public void run() {
            Log.d("XXX", "Requesting Notification count from server ...");
            EMRestClient.getmEMRestService().getNotificationCount(new Callback<NotificationCount>() {
                @Override
                public void success(NotificationCount response, Response unused) {

                    int unreadNotifCount = response.getCount();

                    Log.d("XXX", "Successfully fetched notification count, unread = " + response.getCount());
                    if (unreadNotifCount>0){
                        // call listener to repaint menu
                        for (NewNotificationListener x :notifListeners){
                            x.onNewNotificationReceived(response.getCount());    
                        }
                    }
                }

                @Override
                public void failure(RetrofitError error) {
                    Log.d("XXX", "Failed to fetch notification count from server");
                }
            });

        }
    }


}

代码的改进部分在这里：

    @POST("/notification/notification_count/")
    void getNotificationCount(Callback<NotificationCount> callback);

Answer 1

我目前正在android中开发类似的东西。看看这是否对您有帮助：

ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(1);
executor.scheduleAtFixedRate(getReloadTask(position), 0, 20, TimeUnit.SECONDS);