启用 DPI 缩放后，QPushButton 的图标模糊

Question

我发现启用DPI缩放后QPushButon的图标模糊不清。即使换成 SVG，图标依然模糊。有什么办法可以让图标更清晰吗？

代码如下：

# coding:utf-8
import os
import sys

from PyQt5.QtGui import QIcon
from PyQt5.QtWidgets import QApplication, QPushButton, QWidget


class Demo(QWidget):

    def __init__(self):
        super().__init__(parent=None)
        self.button = QPushButton(' Shuffle all', self)
        imagePath = "app/resource/images/random_play_all/Shuffle_normal.png"
        self.button.setIcon(QIcon(imagePath))
        self.button.move(self.width()//2-self.button.width() //
                         2, self.height()//2-self.button.height()//2)


if __name__ == '__main__':
    os.environ["QT_ENABLE_HIGHDPI_SCALING"] = "0"
    os.environ["QT_SCALE_FACTOR"] = '1.25'
    app = QApplication(sys.argv)
    demo = Demo()
    demo.show()
    app.exec_()

运行结果如下图

Answer 1

我通过重写 QIconEngine 和设置 Qt.AA_UseHighDpiPixmaps 标志解决了这个问题。

# coding:utf-8
import os
import sys

from PyQt5.QtCore import QPoint, QRect, QSize, Qt
from PyQt5.QtGui import QIcon, QIconEngine, QImage, QPainter, QPixmap
from PyQt5.QtWidgets import QApplication, QPushButton, QWidget



class PixmapIconEngine(QIconEngine):
    """ Pixmap icon engine """

    def __init__(self, iconPath: str):
        self.iconPath = iconPath
        super().__init__()

    def paint(self, painter: QPainter, rect: QRect, mode: QIcon.Mode, state: QIcon.State):
        painter.setRenderHints(QPainter.Antialiasing |
                               QPainter.SmoothPixmapTransform)
        painter.drawImage(rect, QImage(self.iconPath))

    def pixmap(self, size: QSize, mode: QIcon.Mode, state: QIcon.State) -> QPixmap:
        pixmap = QPixmap(size)
        pixmap.fill(Qt.transparent)
        self.paint(QPainter(pixmap), QRect(QPoint(0, 0), size), mode, state)
        return pixmap


class Icon(QIcon):

    def __init__(self, iconPath: str):
        self.iconPath = iconPath
        super().__init__(PixmapIconEngine(iconPath))


class Demo(QWidget):

    def __init__(self):
        super().__init__(parent=None)
        self.button = QPushButton(' Shuffle all', self)
        imagePath = "resource/images/random_play_all/Shuffle_normal.png"
        self.button.setIcon(Icon(imagePath))
        self.button.move(self.width()//2-self.button.width() //
                         2, self.height()//2-self.button.height()//2)


if __name__ == '__main__':
    os.environ["QT_ENABLE_HIGHDPI_SCALING"] = "0"
    os.environ["QT_SCALE_FACTOR"] = '1.25'
    QApplication.setAttribute(Qt.AA_UseHighDpiPixmaps)
    app = QApplication(sys.argv)
    demo = Demo()
    demo.show()
    app.exec_()

这是结果

启用 DPI 缩放后，QPushButton 的图标模糊

The icon of QPushButton is blurry when DPI scaling is enabled

python

qt

pyqt

qpushbutton