Question

I have created blank project and try do next code. Unfortunately I got problem:
Main activity does’t load while don’t finish my thread. If don’t use return value from thread all work normal.
unfortunately
final ExecutorService service;
final Future task;

    service = Executors.newFixedThreadPool(1);
    task    = service.submit(new Foo());


    try
    {
        final String str;

        // waits the 10 seconds for the Callable.call to finish.
        str = task.get();
        Log.d("VSK",str);
    }
    catch(final InterruptedException ex)
    {
        ex.printStackTrace();
    }
    catch(final ExecutionException ex)
    {
        ex.printStackTrace();
    }

    service.shutdownNow();

}
class Foo
        implements Callable<String>
{
    public String call()
    {
        try
        {
            // sleep for 10 seconds
            Thread.sleep(10 * 1000);
        }
        catch(final InterruptedException ex)
        {
            ex.printStackTrace();
        }

        return ("Hello, World!");
    }
}

Answer 1

This line str = task.get(); blocks main thead while your callable being executed in other thread. Return result from your task via Handler or use AsyncTask.