pyqt async sevensegment example using quamash.QEventLoop and max7219

async-pyqt-sevensegment.py

import sys
import time
import asyncio

from PyQt5.QtWidgets import (QApplication, QProgressBar, QMainWindow, QSlider,
    QVBoxLayout, QWidget)

from quamash import QEventLoop, QThreadExecutor

import max7219.led as led


class MainWindow(QMainWindow):
    def __init__(self):
        super(MainWindow, self).__init__()

        self.progress = QProgressBar()
        self.progress.setRange(0, 99)
        self.progress.show()

        self.slider = QSlider()
        self.slider.show()

        # set layout
        self.layout = QVBoxLayout()
        self.layout.addWidget(self.progress)
        self.layout.addWidget(self.slider)

        self.win = QWidget()
        self.win.resize(320, 240)
        self.win.setLayout(self.layout)
        self.win.show()

        self.device = led.sevensegment()
        self.device.clear()

        with loop:
            # context manager calls .close() when loop completes,
            # and releases all resources
            loop.run_until_complete(self.master())

    @asyncio.coroutine
    def master(self):
        yield from self.first_50()
        with QThreadExecutor(1) as exec:
            yield from loop.run_in_executor(exec, self.last_50)
        print('ready!')

    def updateValue(self, val):
        self.progress.setValue(val)
        self.device.write_text(0, str(val))

    @asyncio.coroutine
    def first_50(self):
        for i in range(50):
            self.updateValue(i)
            yield from asyncio.sleep(.1)

    def last_50(self):
        for i in range(50, 100):
            loop.call_soon_threadsafe(self.updateValue, i)
            time.sleep(.1)

if __name__ == '__main__':
    app = QApplication(sys.argv)
    loop = QEventLoop(app)
    asyncio.set_event_loop(loop)

    main = MainWindow()
    main.show()