Android Callable

Question

如何实现Callable返回布尔值并做一些事情？

我需要使用外部线程连接到FTP服务器,我不能在主要活动中执行此操作,我需要返回值才能知道它是否已连接;

[主要活动]

public class doSomething implements Callable<Boolean> {

   @Override
   public Boolean call() throws Exception {
       // TODO something...
       return value;
   }

}

public void onClick(View view) {
    ExecutorService executor = Executors.newFixedThreadPool(1);
    FutureTask<Boolean> futureTask = new FutureTask<Boolean>(new doSomething());
    executor.execute(futureTask);
}

Answer 1

您可以像在任何其他Java程序中一样使用Android中的Callable,即

    ExecutorService executor = Executors.newFixedThreadPool(1);
    final Future<Boolean> result = executor.submit(callable);
    boolean value = result.get()

但请注意,get()方法会阻止不推荐的主线程.

对于您的用例,您应该使用AsyncTask.例如,

public class FTPConnection extends AsyncTask<Void, Void, Boolean> {

    @Override
    protected boolean doInBackground(Void... params) {
          //Connect to FTP
    }

    @Override
    protected void onPostExecute(boolean connected) {
         //Take action based on result
    }
}