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Python pyqt (gui) example 'analogclock'
analogclock
Python pyqt example: analogclock
#!/usr/bin/env python
#############################################################################
##
## Copyright (C) 2013 Riverbank Computing Limited.
## Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
## All rights reserved.
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## This file is part of the examples of PyQt.
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## $QT_BEGIN_LICENSE:BSD$
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## the names of its contributors may be used to endorse or promote
## products derived from this software without specific prior written
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## $QT_END_LICENSE$
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#############################################################################
from PyQt5.QtCore import (pyqtProperty, pyqtSignal, pyqtSlot, QPoint, QSize,
Qt, QTime, QTimer)
from PyQt5.QtGui import QBrush, QColor, QPainter, QPen, QPolygon
from PyQt5.QtWidgets import QApplication, QWidget
class PyAnalogClock(QWidget):
"""PyAnalogClock(QWidget)
Provides an analog clock custom widget with signals, slots and properties.
The implementation is based on the Analog Clock example provided with both
Qt and PyQt.
"""
# Emitted when the clock's time changes.
timeChanged = pyqtSignal(QTime)
# Emitted when the clock's time zone changes.
timeZoneChanged = pyqtSignal(int)
def __init__(self, parent=None):
super(PyAnalogClock, self).__init__(parent)
self.timeZoneOffset = 0
timer = QTimer(self)
timer.timeout.connect(self.update)
timer.timeout.connect(self.updateTime)
timer.start(1000)
self.setWindowTitle("Analog Clock")
self.resize(200, 200)
self.hourHand = QPolygon([
QPoint(7, 8),
QPoint(-7, 8),
QPoint(0, -40)
])
self.minuteHand = QPolygon([
QPoint(7, 8),
QPoint(-7, 8),
QPoint(0, -70)
])
self.hourColor = QColor(0, 127, 0)
self.minuteColor = QColor(0, 127, 127, 191)
def paintEvent(self, event):
side = min(self.width(), self.height())
time = QTime.currentTime()
time = time.addSecs(self.timeZoneOffset * 3600)
painter = QPainter()
painter.begin(self)
painter.setRenderHint(QPainter.Antialiasing)
painter.translate(self.width() / 2, self.height() / 2)
painter.scale(side / 200.0, side / 200.0)
painter.setPen(Qt.NoPen)
painter.setBrush(QBrush(self.hourColor))
painter.save()
painter.rotate(30.0 * ((time.hour() + time.minute() / 60.0)))
painter.drawConvexPolygon(self.hourHand)
painter.restore()
painter.setPen(self.hourColor)
for i in range(0, 12):
painter.drawLine(88, 0, 96, 0)
painter.rotate(30.0)
painter.setPen(Qt.NoPen)
painter.setBrush(QBrush(self.minuteColor))
painter.save()
painter.rotate(6.0 * (time.minute() + time.second() / 60.0))
painter.drawConvexPolygon(self.minuteHand)
painter.restore()
painter.setPen(QPen(self.minuteColor))
for j in range(0, 60):
if (j % 5) != 0:
painter.drawLine(92, 0, 96, 0)
painter.rotate(6.0)
painter.end()
def minimumSizeHint(self):
return QSize(50, 50)
def sizeHint(self):
return QSize(100, 100)
def updateTime(self):
self.timeChanged.emit(QTime.currentTime())
# The timeZone property is implemented using the getTimeZone() getter
# method, the setTimeZone() setter method, and the resetTimeZone() method.
# The getter just returns the internal time zone value.
def getTimeZone(self):
return self.timeZoneOffset
# The setTimeZone() method is also defined to be a slot. The @pyqtSlot
# decorator is used to tell PyQt which argument type the method expects,
# and is especially useful when you want to define slots with the same
# name that accept different argument types.
@pyqtSlot(int)
def setTimeZone(self, value):
self.timeZoneOffset = value
self.timeZoneChanged.emit(value)
self.update()
# Qt's property system supports properties that can be reset to their
# original values. This method enables the timeZone property to be reset.
def resetTimeZone(self):
self.timeZoneOffset = 0
self.timeZoneChanged.emit(0)
self.update()
# Qt-style properties are defined differently to Python's properties.
# To declare a property, we call pyqtProperty() to specify the type and,
# in this case, getter, setter and resetter methods.
timeZone = pyqtProperty(int, getTimeZone, setTimeZone, resetTimeZone)
if __name__ == "__main__":
import sys
app = QApplication(sys.argv)
clock = PyAnalogClock()
clock.show()
sys.exit(app.exec_())
Useful links
- Learn PyQt: https://pythonbasics.org/pyqt-hello-world/
- Install PyQt: https://pythonbasics.org/install-pyqt/