from PyQt5 import QtWidgets, QtCore, QtGui

class ColorInput(QtWidgets.QLineEdit):

    def __init__(self, init_color: QtGui.QColor, parent):
        super().__init__(parent)
        self.setReadOnly(True)
        self.installEventFilter(self)
        self._color = init_color
        self.update(init_color)
        self._is_editing = False

    def eventFilter(self, source, event):
        if source is self and event.type() == QtCore.QEvent.FocusIn:
            if not self._is_editing:
                self._is_editing = True
                color = QtWidgets.QColorDialog.getColor(self._color, self)
                if color.isValid():
                    self.update(color)
            else:
                self._is_editing = False
                self.clearFocus()
        return super(ColorInput, self).eventFilter(source, event)

    def update(self, color: QtGui.QColor):
        self._color = color
        self.setText(color.name().upper())
        palette = QtGui.QPalette()
        palette.setColor(QtGui.QPalette.Base, color)
        palette.setColor(QtGui.QPalette.Text, color)
        self.setPalette(palette)