PyQt5 QDoubleSpinBox - Setting the Step Type Attribute

PyQt5 is a Python module that allows developers to create desktop applications with a graphical user interface (GUI). One of the many widgets available in PyQt5 is the QDoubleSpinBox, which allows users to enter and manipulate decimal values.

The QDoubleSpinBox widget has a variety of properties that can be set to customize its behavior. One such property is the stepType, which determines how the widget responds to user input when the up and down arrows are clicked.

The stepType Property

The stepType property has two possible values: QAbstractSpinBox.AdaptiveDecimalStepType and QAbstractSpinBox.DefaultStepType. When the stepType is set to QAbstractSpinBox.AdaptiveDecimalStepType, the widget adjusts the step size based on the current value. This means that the value will be incremented or decremented by smaller amounts when the slider is close to the minimum or maximum values.

spinbox.setStepType(QAbstractSpinBox.AdaptiveDecimalStepType)

When the stepType is set to QAbstractSpinBox.DefaultStepType, the widget uses a fixed step size for all values. This means that the value will be incremented or decremented by the same amount, regardless of its current position.

spinbox.setStepType(QAbstractSpinBox.DefaultStepType)

Example

Here is an example that demonstrates how to set the stepType property of a QDoubleSpinBox widget:

from PyQt5.QtWidgets import QApplication, QWidget, QDoubleSpinBox, QVBoxLayout
import sys


class Example(QWidget):

    def __init__(self):
        super().__init__()

        self.initUI()

    def initUI(self):

        vbox = QVBoxLayout()

        spinbox1 = QDoubleSpinBox()
        spinbox1.setRange(-10, 10)
        spinbox1.setSingleStep(0.1)
        spinbox1.setStepType(QAbstractSpinBox.AdaptiveDecimalStepType)

        spinbox2 = QDoubleSpinBox()
        spinbox2.setRange(-10, 10)
        spinbox2.setSingleStep(0.1)
        spinbox2.setStepType(QAbstractSpinBox.DefaultStepType)

        vbox.addWidget(spinbox1)
        vbox.addWidget(spinbox2)

        self.setLayout(vbox)

        self.setGeometry(300, 300, 300, 150)
        self.setWindowTitle('QDoubleSpinBox Example')
        self.show()


if __name__ == '__main__':

    app = QApplication(sys.argv)
    ex = Example()
    sys.exit(app.exec_())

In this example, we create a QWidget with two QDoubleSpinBox widgets. The first spinbox has its stepType property set to QAbstractSpinBox.AdaptiveDecimalStepType, while the second spinbox has its stepType property set to QAbstractSpinBox.DefaultStepType. When the user clicks the up or down arrow on each spinbox, they will notice that the step size changes depending on the current value of the spinbox in the first case, while it remains fixed in the second case.

Conclusion

The QDoubleSpinBox widget is a useful tool for accepting decimal input from users in desktop applications built with PyQt5. By adjusting the stepType property of the widget, developers can customize how the spinbox responds to user input and make their applications more user-friendly.