PyQt5 QSpinBox – 为下降按钮添加皮肤

以下是Python中PyQt5 QSpinBox为下降按钮添加皮肤的完整使用攻略：

1. 概述

PyQt5是一个非常流行的Python GUI框架，而QSpinBox在PyQt5中是一种非常常用的小部件，通常使用于数字调节。QSpinBox提供了增加和减少按钮来调节数值，而QSpinBox的皮肤同样也可以进行更改。

2. 添加皮肤

要为QSpinBox的下降按钮添加皮肤，我们需要先创建一个QStyle，然后使用该QStyle创建Edit按钮（在QSpinBox中，下降按钮是一个Edit按钮）。下面是添加皮肤的代码：

from PyQt5.QtWidgets import QApplication, QSpinBox, QStyleFactory

app = QApplication([])
spinBox = QSpinBox()
# 创建QStyle
style = QStyleFactory.create('Fusion')
# 获取QSpinBox的下降按钮
downButton = spinBox.findChild(QAbstractButton)
# 为按钮设置皮肤
option_down = spinBox.style().standardIcon(QStyle.SP_ArrowDown, None, downButton)
option_downrect = spinBox.style().subControlRect(QStyle.CC_SpinBox, downButton, QStyle.SC_SpinBoxArrow, spinBox)
painter = QtGui.QPainter(downButton)
painter.drawPixmap(option_downrect, option_down.pixmap(option_down.availableSizes()[0]), option_downrect)
painter.end()

3. 示例说明

下面将使用两个示例来演示如何为QSpinBox的下降按钮添加皮肤。

示例1：替换下降按钮为图片

import sys
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QIcon, QPixmap
from PyQt5.QtWidgets import QApplication, QSpinBox, QAbstractButton, QStyle, QStyleFactory


class Example(QWidget):

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

    def initUI(self):
        # 创建QApplication
        app = QApplication(sys.argv)

        # 创建spinBox
        spinBox = QSpinBox()
        spinBox.move(30, 50)
        spinBox.resize(80, 30)

        # 创建QStyle
        style = QStyleFactory.create('Fusion')

        # 获取QSpinBox的下降按钮
        downButton = spinBox.findChild(QAbstractButton)

        # 创建QPixmap对象
        option_down = QPixmap("down.png")

        # 设置按钮皮肤
        option_downrect = spinBox.style().subControlRect(QStyle.CC_SpinBox, downButton, QStyle.SC_SpinBoxArrow, spinBox)
        painter = QtGui.QPainter(downButton)
        painter.drawPixmap(option_downrect, option_down)
        painter.end()

        self.setGeometry(300, 300, 250, 150)
        self.setWindowTitle('QSpinBox')
        self.show()

        sys.exit(app.exec_())


if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = Example()
    sys.exit(app.exec_())

示例2：自定义下降按钮样式

import sys
from PyQt5.QtCore import Qt
from PyQt5.QtGui import QIcon, QPixmap
from PyQt5.QtWidgets import QApplication, QSpinBox, QAbstractButton, QStyleFactory, QStyle


class MySpinBox(QSpinBox):
    def __init__(self, parent=None):
        super().__init__(parent=parent)
        self.initUI()

    def initUI(self):
        # 创建QStyle
        style = QStyleFactory.create('Fusion')

        # 获取下降按钮
        downButton = self.findChild(QAbstractButton)

        self.downButtonPixmap = QPixmap('down.png')
        self.downButtonSize = self.maximumHeight() - 5

        self.setFixedWidth(self.maximumWidth() + self.downButtonSize)

    def paintEvent(self, event):
        # 绘制按钮上的图标
        painter = QtGui.QPainter(self)
        downButtonRect = QtCore.QRect(0, 0, self.downButtonSize, self.downButtonSize)
        painter.drawPixmap(downButtonRect, self.downButtonPixmap)
        painter.end()

        super(MySpinBox, self).paintEvent(event)


if __name__ == '__main__':
    app = QApplication(sys.argv)
    mySpinBox = MySpinBox()
    mySpinBox.show()
    sys.exit(app.exec_())

上述示例代码中的down.png为控件下降链接防伪戏做的样例图，皮肤的实现方式可以自己选择。