widgets.py 文件源码

def watch_queue(self, queue, callback, flags=zmq.POLLIN):
        """
        Call *callback* when zmq *queue* has something to read (when *flags* is
        set to ``POLLIN``, the default) or is available to write (when *flags*
        is set to ``POLLOUT``). No parameters are passed to the callback.

        :param queue:
            The zmq queue to poll.

        :param callback:
            The function to call when the poll is successful.

        :param int flags:
            The condition to monitor on the queue (defaults to ``POLLIN``).
        """
        if queue in self._queue_callbacks:
            raise ValueError('already watching %r' % queue)
        self._poller.register(queue, flags)
        self._queue_callbacks[queue] = callback
        return queue