Easy threading and multiprocessing for GUI applications
async_gui is a library aimed to make use of threads in GUI applications simpler. It’s inspired by PyCon talk Using futures for async GUI programming in Python 3.3 and tornado @gen.engine implementation.
Most of GUI toolkits don’t allow you to access graphical elements from non-GUI thread. Python 3.2+ has nice new feature concurrent.futures, but we can’t just wait for result from future and callbacks are not very handy.
Combination of Coroutines via Enhanced Generators (PEP-342) and futures creates a rich and easy to use asynchronous programming model which can be used for creating highly responsive GUI applications.
Demo of button click handler:
@engine.async def on_button_click(self, *args): self.status_label.setText("Downloading image...") # Run single task in separate thread image_data = yield Task(self.load_url, "http://www.google.com/images/srpr/logo4w.png") pixmap = QtGui.QPixmap.fromImage(QtGui.QImage.fromData(image_data)) self.image_label.setPixmap(pixmap) self.status_label.setText("Downloading pages...") urls = ['http://www.google.com', 'http://www.yandex.ru', 'http://www.python.org'] # Run multiple task simultaneously in thread pool pages = yield [Task(self.load_url, url) for url in urls] self.status_label.setText("Done") avg_size = sum(map(len, pages)) / len(pages) self.result_label.setText("Average page size: %s" % avg_size)
Tasks yielded from on_button_click() executed in thread pool, but GUI updates done in the GUI thread. For CPU-bound applications there is also ability to run tasks in pool of processes.
$ pip install async_gui
Or download, unpack and:
$ python setup.py install
To run tests use:
$ python setup.py test
- MultiTask can return generator of ready tasks instead waiting for all done
- initial PyPI release