Prerequisite: Introduction to pyqt-5
A clock or watch is called “analog” when it has moving hands and (usually) hours marked from number 1 to 12 to show you the time. Some have Roman Numerals (I, II, III, etc) instead, or no numbers at all! In other words: not a digital clock.
PyQt5 is a cross-platform GUI toolkit, a set of python bindings for Qt v5. One can develop an interactive desktop application with so much ease because of the tools and simplicity provided by this library. A GUI application consists of Front-end and Back-end.
Approach :
- Create a Clock class which inherits the QMainWindow class.
- Inside the Clock class creating a timer object which updates the whole code after each second.
- Create three polygon objects for each hand of the clock .
- Create a paint event method.
- Inside the paint event method get the current time and the minimum of windows width or height .
- Create a painter object and a method to draw the hands.
- Inside the method for drawing hands(pointer) take arguments like color, rotation and polygon object.
- Rotate the painter object and draw the pointer.
- Inside the paint event method, according to the current time set the rotation value and call the draw pointer method.
- Draw the background image of the clock i.e lines for each hour.
Below is the implementation :
Python3
# importing librariesfrom PyQt5.QtWidgets import *from PyQt5 import QtCore, QtGuifrom PyQt5.QtGui import *from PyQt5.QtCore import *import sys# creating a clock classclass Clock(QMainWindow): # constructor def __init__(self): super().__init__() # creating a timer object timer = QTimer(self) # adding action to the timer # update the whole code timer.timeout.connect(self.update) # setting start time of timer i.e 1 second timer.start(1000) # setting window title self.setWindowTitle('Clock') # setting window geometry self.setGeometry(200, 200, 300, 300) # setting background color to the window self.setStyleSheet("background : black;") # creating hour hand self.hPointer = QtGui.QPolygon([QPoint(6, 7), QPoint(-6, 7), QPoint(0, -50)]) # creating minute hand self.mPointer = QPolygon([QPoint(6, 7), QPoint(-6, 7), QPoint(0, -70)]) # creating second hand self.sPointer = QPolygon([QPoint(1, 1), QPoint(-1, 1), QPoint(0, -90)]) # colors # color for minute and hour hand self.bColor = Qt.green # color for second hand self.sColor = Qt.red # method for paint event def paintEvent(self, event): # getting minimum of width and height # so that clock remain square rec = min(self.width(), self.height()) # getting current time tik = QTime.currentTime() # creating a painter object painter = QPainter(self) # method to draw the hands # argument : color rotation and which hand should be pointed def drawPointer(color, rotation, pointer): # setting brush painter.setBrush(QBrush(color)) # saving painter painter.save() # rotating painter painter.rotate(rotation) # draw the polygon i.e hand painter.drawConvexPolygon(pointer) # restore the painter painter.restore() # tune up painter painter.setRenderHint(QPainter.Antialiasing) # translating the painter painter.translate(self.width() / 2, self.height() / 2) # scale the painter painter.scale(rec / 200, rec / 200) # set current pen as no pen painter.setPen(QtCore.Qt.NoPen) # draw each hand drawPointer(self.bColor, (30 * (tik.hour() + tik.minute() / 60)), self.hPointer) drawPointer(self.bColor, (6 * (tik.minute() + tik.second() / 60)), self.mPointer) drawPointer(self.sColor, (6 * tik.second()), self.sPointer) # drawing background painter.setPen(QPen(self.bColor)) # for loop for i in range(0, 60): # drawing background lines if (i % 5) == 0: painter.drawLine(87, 0, 97, 0) # rotating the painter painter.rotate(6) # ending the painter painter.end()# Driver codeif __name__ == '__main__': app = QApplication(sys.argv) # creating a clock object win = Clock() # show win.show() exit(app.exec_()) |
Output:
