Uploaded August 2024 | Updated September 2026, 1 week ago

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#python #pythontutorial #pythoncourse

00:00:00 intro
00:00:16 pip install PyQt5
00:00:37 imports
00:01:56 class Stopwatch(QWidget)
00:02:28 if __name__
00:03:54 START HERE
00:05:57 method declarations
00:06:55 initUI()
00:09:40 setStyleSheet()
00:12:28 signals and slots
00:13:33 methods definitions

# Python PyQt5 Stopwatch
import sys
from PyQt5.QtWidgets import (QApplication, QWidget, QLabel,
QPushButton, QVBoxLayout, QHBoxLayout)
from PyQt5.QtCore import QTimer, QTime, Qt

class Stopwatch(QWidget):
def __init__(self):
super().__init__()
self.time = QTime(0, 0, 0, 0)
self.time_label = QLabel("00:00:00.00", self)
self.start_button = QPushButton("Start", self)
self.stop_button = QPushButton("Stop", self)
self.reset_button = QPushButton("Reset", self)
self.timer = QTimer(self)
self.initUI()

def initUI(self):
self.setWindowTitle("Stopwatch")

vbox = QVBoxLayout()
vbox.addWidget(self.time_label)

self.setLayout(vbox)

self.time_label.setAlignment(Qt.AlignCenter)

hbox = QHBoxLayout()

hbox.addWidget(self.start_button)
hbox.addWidget(self.stop_button)
hbox.addWidget(self.reset_button)

vbox.addLayout(hbox)

self.setStyleSheet("""
QPushButton, QLabel{
padding: 20px;
font-weight: bold;
font-family: calibri;
}
QPushButton{
font-size: 50px;
}
QLabel{
font-size: 120px;
background-color: hsl(200, 100%, 85%);
border-radius: 20px;
}
""")

self.start_button.clicked.connect(self.start)
self.stop_button.clicked.connect(self.stop)
self.reset_button.clicked.connect(self.reset)
self.timer.timeout.connect(self.update_display)

def start(self):
self.timer.start(10)

def stop(self):
self.timer.stop()

def reset(self):
self.timer.stop()
self.time = QTime(0, 0, 0, 0)
self.time_label.setText(self.format_time(self.time))

def format_time(self, time):
hours = time.hour()
minutes = time.minute()
seconds = time.second()
milliseconds = time.msec() // 10
return f"{hours:02}:{minutes:02}:{seconds:02}.{milliseconds:02}"

def update_display(self):
self.time = self.time.addMSecs(10)
self.time_label.setText(self.format_time(self.time))

if ___name___ == "__main__":
app = QApplication(sys.argv)
stopwatch = Stopwatch()
stopwatch.show()
sys.exit(app.exec_())