QDoubleSpinBox¶
QDoubleSpinBox class provides a double spin box widget that lets you select and control mistakes.
For further details, check QDoubleSpinBox official document .
Example¶
import sys
from PyQt5.QtWidgets import QApplication, QWidget, QLabel, QDoubleSpinBox, QVBoxLayout
class MyApp(QWidget):
def __init__(self):
super().__init__()
self.initUI()
def initUI(self):
self.lbl1 = QLabel('QDoubleSpinBox')
self.dspinbox = QDoubleSpinBox()
self.dspinbox.setRange(0, 100)
self.dspinbox.setSingleStep(0.5)
self.dspinbox.setPrefix('$ ')
self.dspinbox.setDecimals(1)
self.lbl2 = QLabel('$ 0.0')
self.dspinbox.valueChanged.connect(self.value_changed)
vbox = QVBoxLayout()
vbox.addWidget(self.lbl1)
vbox.addWidget(self.dspinbox)
vbox.addWidget(self.lbl2)
vbox.addStretch()
self.setLayout(vbox)
self.setWindowTitle('QDoubleSpinBox')
self.setGeometry(300, 300, 300, 200)
self.show()
def value_changed(self):
self.lbl2.setText('$ '+str(self.dspinbox.value()))
if __name__ == '__main__':
app = QApplication(sys.argv)
ex = MyApp()
sys.exit(app.exec_())
Two labels(self.lbl1, self.lbl2) and a double spin box widget(self.spinbox) appear on the window.
Description¶
self.dspinbox = QDoubleSpinBox()
self.dspinbox.setRange(0, 100)
self.dspinbox.setSingleStep(0.5)
Make a QDoubleSpinBox object(self.dspinbox).
setRange() method helps you limit the range of selection. By default, the minimum value is 0.0 and the maximum is 99.99.
Use setSingleStep() method to make a single step 0.5.
self.dspinbox.setPrefix('$ ')
self.dspinbox.setDecimals(1)
setPrefix() to sets the character that will come in front of the number. setSuffix() makes the character come behind the number.
setDecimals() sets the number of decimal places to be displayed.
self.dspinbox.valueChanged.connect(self.value_changed)
Associate the signal that occurs when the value of the double spin box widget is changed (valueChanged) with the self.value_changed method.
vbox = QVBoxLayout()
vbox.addWidget(self.lbl1)
vbox.addWidget(self.dspinbox)
vbox.addWidget(self.lbl2)
vbox.addStretch()
self.setLayout(vbox)
Use the vertical box layout to place two labels and a double-spin box widget vertically, and set it as the layout of the entire widget.
def value_changed(self):
self.lbl2.setText('$ '+str(self.dspinbox.value()))
When the value of the double spin box changes, make the text of self.lbl2 be the value for the double spin box (self.dspinbox.value()).
