[FIXED] How to change the style of a specific action in the menu?

Issue

its form discord

I want to do something like this in QMenu for my tray icon. How can this be implemented in pyqt5?

Solution

It can be achieved with custom style that proxies draw calls and modifies palette for specific menu items. Items can be identified by text in QStyleOptionMenuItem. For this solution to work application must have non-native style (for example "Fusion") and no stylesheet must be defined for this menu.

from PyQt5 import QtWidgets, QtCore, QtGui
import sys

class Style(QtWidgets.QProxyStyle):
    def __init__(self, style = None):
        super().__init__(style)
        self._colors = dict()

    def setColor(self, text, color):
        self._colors[text] = color

    def drawControl(self, element, option, painter, widget):
        if element == QtWidgets.QStyle.CE_MenuItem:
            text = option.text
            option_ = QtWidgets.QStyleOptionMenuItem(option)
            if text in self._colors:
                color = self._colors[text]
            else:
                color = QtGui.QColor("#A9BBAE")
            option_.palette.setColor(QtGui.QPalette.Text, color)
            return self.baseStyle().drawControl(element, option_, painter, widget)
        return self.baseStyle().drawControl(element, option, painter, widget)

class MenuStyler():
    def __init__(self, menu):
        style = Style()
        style.setBaseStyle(menu.style())
        menu.setStyle(style)
        self._style = style
        self._menu = menu

    def setColor(self, key, color):
        if isinstance(key, str):
            self._style.setColor(key, color)
        elif isinstance(key, int):
            text = self._menu.actions()[key].text()
            self._style.setColor(text, color)
        else:
            raise ValueError("Key must be either int or string")

if __name__ == "__main__":
    
    app = QtWidgets.QApplication(sys.argv)

    app.setStyle(QtWidgets.QStyleFactory.create("Fusion"))

    palette = app.palette()
    palette.setColor(QtGui.QPalette.Base, QtGui.QColor("#18191C"))
    palette.setColor(QtGui.QPalette.Text, QtGui.QColor("#A9BBAE"))
    palette.setColor(QtGui.QPalette.WindowText, QtGui.QColor("#A9BBAE"))
    palette.setColor(QtGui.QPalette.ButtonText, QtGui.QColor("#A9BBAE"))
    app.setPalette(palette)

    menu = QtWidgets.QMenu()
    menu.addAction("Mark As Read")
    menu.addSeparator()
    menu.addAction("Invite People")
    submenuMute = menu.addMenu("MuteServer")

    submenuMute.addAction("submenu")

    hideMuted = QtWidgets.QAction("Hide Muted Channels")
    hideMuted.setCheckable(True)
    menu.addAction(hideMuted)
    menu.addSeparator()
    menu.addAction("Leave Server")

    styler = MenuStyler(menu)
    styler.setColor("Invite People", QtGui.QColor("#3D6BC4"))
    styler.setColor("Leave Server", QtGui.QColor("#F04544"))
    
    menu.exec(QtCore.QPoint(100,100))

    app.exec()

Answered By - mugiseyebrows