Integrate eventlet with Qt's eventloop. It is very simple to use: from hgoldfish.utils import eventlet app = QApplication() eventlet.start_application() After starting the Qt's eventloop, we can make connections as in select-based eventlet applications. from eventlet.green import urllib def fetchUrl(url): page = urllib.urlopen(url).read() print(page) A complete simple example: ``` import logging; logging.basicConfig(level = logging.DEBUG) from hgoldfish.utils import eventlet from eventlet.green import urllib from PyQt4.QtCore import Qt from PyQt4.QtGui import QApplication, QTextBrowser

class TestWidget(QTextBrowser): def init(self): QTextBrowser.init(self) self.operations = eventlet.GreenletGroup()

def mousePressEvent(self, event):
    if event.button() == Qt.MidButton:
        self.operations.spawn(self.getpage)
    QTextBrowser.mousePressEvent(self, event)

def getpage(self):
    page = urllib.urlopen("http://code.google.com/p/eventlet-pyqt/").read().decode("utf-8")
    self.setHtml(page)

app = QApplication([]) w = TestWidget() w.show() eventlet.start_application(quitOnLastWindowClosed = True) ``` Unfortunely, as the greenlet module is broken, we must be very careful to spawn greenlets.

1. DO NOT throw any exceptions from greenlet. Or that Python will crash.
2. Greenlets SHOULD NOT keep references to its owner. As this situation causes cycled references.If you want to do so, use weakref, or give a try to GreenletGroup, which pass the weak reference of parameters to target function.
3. DO NOT start a local Qt eventloop. If you want to do so, use runLocalLoop(). Pay attention to QMessageBox and QDialog.
4. Clear exceptions before yield to another greenlet. The Python provide sys.exc_clar() to do so.

This module provide this functions:

• runInNewThread(func, *args, **kwargs)

  Start a new thread to run func with arguments provided. Block current greenlet, wait for the new thread to finished, and return the value func returned.

• start_application(quitOnLastWindowClosed = True)

  Start the Qt Application.

• stop_application()

  Stop the Qt Application. Wait 1 second for greenlets to stop.

• exc_clear()

  For Python 2.x version, it is sys.exc_clear(). For Python 3.x, it does nothing.

• runLocalLoop(eventloop) & runDialog(dialog)

  Alias for callMethodInEventLoop(eventloop.exec)

• callMethodInEventLoop(func, *args, **kwargs)

  Dialogs and local eventloops must run in the greenlet where Qt's main eventloop live in.

The GreenletGroup manages greenlets. It has several methods you may like.

• spawnWithName(name, func, *args, **kwargs)

  Spawn a new greenlet named name to run the given func with past arguments. All the arguments are past as weakref.proxy.

• spawn(func, *args, **kwargs)

  Alias for spawnWithName(None, func, *args, **kwargs)

• get(name)

  Get the greenlet which named name.

• kill(name)

  Kill the greenlet which named name

• killall()

  Kill all managed greenlets.