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copied!<p>You can use a Qt IDLE "timer" to allow <code>gevent</code> for processing its microthreads while no Qt events handled for a short period of time, for example 10 milliseconds. It is still not perfect, since it does not give the "smoothest" possible integration. It is because we don't use a single event loop for both Qt and gevent, just "interleaving" them in time.</p> <p>The correct solution would be to allow libevent to listen on new Qt events somehow, but I haven't been able to figure out how to do that in practice yet. Maybe having Qt to send something to gevent via a socket when a GUI event arrives into the event queue would help. Has anybody solved that?</p> <p>Working example:</p> <pre><code>""" Qt - gevent event loop integration using a Qt IDLE timer """ import sys, itertools import PySide from PySide import QtCore, QtGui import gevent # Limit the IDLE handler's frequency while still allow for gevent # to trigger a microthread anytime IDLE_PERIOD = 0.01 class MainWindow(QtGui.QMainWindow): def __init__(self, application): QtGui.QMainWindow.__init__(self) self.application = application self.counter = itertools.count() self.resize(400, 100) self.setWindowTitle(u'Counting: -') self.button = QtGui.QPushButton(self) self.button.setText(u'Reset') self.button.clicked.connect(self.reset_counter) self.show() def counter_loop(self): while self.isVisible(): self.setWindowTitle(u'Counting: %d' % self.counter.next()) gevent.sleep(0.1) def reset_counter(self): self.counter = itertools.count() def run_application(self): # IDLE timer: on_idle is called whenever no Qt events left for processing self.timer = QtCore.QTimer() self.timer.timeout.connect(self.on_idle) self.timer.start(0) # Start counter gevent.spawn(self.counter_loop) # Start you application normally, but ensure that you stop the timer try: self.application.exec_() finally: self.timer.stop() def on_idle(self): # Cooperative yield, allow gevent to monitor file handles via libevent gevent.sleep(IDLE_PERIOD) def main(): application = QtGui.QApplication(sys.argv) main_window = MainWindow(application) main_window.run_application() if __name__ == '__main__': main() </code></pre>

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