Android客户端-Java服务器应用程序

Question

I have been working on a client server application the last few days on Android. I choose to use Java socket communication, since i am familiar to it and it seemed easier at the time. I would like to help me though, cos i think that this is not enough for what i want to do.

At the time, as a basic demo application, i am using AsyncTask to connect to my Java Server and exchange text messages in order to arrange an appointment.This is the final goal, an Android app that can be used to book appointments.

I have read that AsyncTask should dont be used for longer period of times, and i would really like the server to sent a message to the client when the time of the appointment is within the next hour or something.

Can i do this using AsyncTask? I think not. From what i have read on the web, AsyncTask freezes the UI till it is done.(that i dont get it, since it is a thread, but anyhow thats what i read).

Would you recomend me using something else than sockets and AsyncTask?

Thanks in advance,ilias

Answer 1

The problem of having a client waiting for a server's message is well known. You are right, keeping the connection open while waiting for a response is not a good idea.

The classical solution is polling. Choose a time interval, connect to the server, ask kindly if the result is already available. If yes, get it and leave. If no, leave and try again later. Of course this is no perfect solution, but many applications are implemented that way.

For the interested reader: Have a look at Web Sockets . The idea is to keep alive a lightweight connection that enables the server to send data without explicit requests of the client. But this seems to be still work in progress.

Answer 2

An async task is fine for what you are doing. I think what you were reading about were applications that need to continuously poll for information from a server like a chat client.