PyQt5: Set font color of custom ComboBox text depending on element selected matching another element in a dataframe

Question

I have the following code:

import sys
from PyQt5 import QtGui, QtCore, QtWidgets
from PyQt5.QtWidgets import *
from PyQt5.QtCore import QSize, Qt, QSortFilterProxyModel, QStringListModel
from PyQt5.QtGui import QIcon, QFont


class ExtendedComboBox(QComboBox):
    def __init__(self, parent=None):
        super(ExtendedComboBox, self).__init__(parent)

        self.setFocusPolicy(Qt.StrongFocus)
        self.setEditable(True)

        # add a filter model to filter matching items
        self.pFilterModel = QSortFilterProxyModel(self)
        self.pFilterModel.setFilterCaseSensitivity(Qt.CaseInsensitive)
        self.pFilterModel.setSourceModel(self.model())

        # add a completer, which uses the filter model
        self.completer = QCompleter(self.pFilterModel, self)
        # always show all (filtered) completions
        self.completer.setCompletionMode(QCompleter.UnfilteredPopupCompletion)
        self.setCompleter(self.completer)

        # connect signals
        self.lineEdit().textEdited.connect(self.pFilterModel.setFilterFixedString)
        self.completer.activated.connect(self.on_completer_activated)


    # on selection of an item from the completer, select the corresponding item from combobox
    def on_completer_activated(self, text):
        if text:
            index = self.findText(text)
            self.setCurrentIndex(index)
            self.activated[str].emit(self.itemText(index))


    # on model change, update the models of the filter and completer as well
    def setModel(self, model):
        super(ExtendedComboBox, self).setModel(model)
        self.pFilterModel.setSourceModel(model)
        self.completer.setModel(self.pFilterModel)


    # on model column change, update the model column of the filter and completer as well
    def setModelColumn(self, column):
        self.completer.setCompletionColumn(column)
        self.pFilterModel.setFilterKeyColumn(column)
        super(ExtendedComboBox, self).setModelColumn(column)

class MainWindow(QMainWindow):

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

        self.setGeometry(100, 100, 800, 600)
        self.centerOnScreen()
        self.combo = ExtendedComboBox(self)
        self.my_list = ['','Option 1', 'Option 2', 'Option 3','Option 4', 'Option 5']
        self.combo.addItems(self.my_list)

        self.combo.setFixedWidth(250)

    def centerOnScreen (self):
        resolution = QDesktopWidget().screenGeometry()
        self.move((resolution.width() / 2) - (self.frameSize().width() / 2),
                  (resolution.height() / 2) - (self.frameSize().height() / 2))

if __name__ == '__main__':

    app = QApplication(sys.argv)
    mainWin = MainWindow()
    mainWin.show()
    sys.exit(app.exec_())

which creates a custom ComboBox with autocomplete from code I have found on Stackoverflow. The selections for the current Combobox consists of the list ['','Option 1', 'Option 2', 'Option 3','Option 4', 'Option 5']

However I would like to know if there is a way to change the font color of the Combobox depending on matches with elements in a dataframe when the Combobox element is updated.

For example, if I have the following dataframe:

    Option number    Color
0    Option 2         Red
1    Option 3         Blue
2    Option 5         Gray

I would like the font color in the Combobox to change to the color indicated when the element selected in the Combobox matches the corresponding one in the dataframe and have the default font color when there is no match.

Is there any way to achieve that in PyQt5?

See https://stackoverflow.com/questions/50711763/pyqt5-combobox-how-do-i-set-the-color-of-currenttext-without-affecting-the-dro — S. Nick, Mar 17 '19 at 12:36
Thank you. It has helped me to come up with a working example. — Sd Junk, Mar 17 '19 at 14:47

score 0 · Answer 1 · answered Mar 17 '19 at 14:52

Here is a working example of the code with help from the thread suggested by @S. Nick:

import sys
from PyQt5 import QtGui, QtCore, QtWidgets
from PyQt5.QtWidgets import *
from PyQt5.QtCore import QSize, Qt, QSortFilterProxyModel, QStringListModel
from PyQt5.QtGui import QIcon, QFont
import pandas as pd
from pandas import DataFrame

class ExtendedComboBox(QComboBox):
    def __init__(self, parent=None):
        super(ExtendedComboBox, self).__init__(parent)

        self.setFocusPolicy(Qt.StrongFocus)
        self.setEditable(True)

        # add a filter model to filter matching items
        self.pFilterModel = QSortFilterProxyModel(self)
        self.pFilterModel.setFilterCaseSensitivity(Qt.CaseInsensitive)
        self.pFilterModel.setSourceModel(self.model())

        # add a completer, which uses the filter model
        self.completer = QCompleter(self.pFilterModel, self)
        # always show all (filtered) completions
        self.completer.setCompletionMode(QCompleter.UnfilteredPopupCompletion)
        self.setCompleter(self.completer)

        # connect signals
        self.lineEdit().textEdited.connect(self.pFilterModel.setFilterFixedString)
        self.completer.activated.connect(self.on_completer_activated)


    # on selection of an item from the completer, select the corresponding item from combobox
    def on_completer_activated(self, text):
        if text:
            index = self.findText(text)
            self.setCurrentIndex(index)
            self.activated[str].emit(self.itemText(index))


    # on model change, update the models of the filter and completer as well
    def setModel(self, model):
        super(ExtendedComboBox, self).setModel(model)
        self.pFilterModel.setSourceModel(model)
        self.completer.setModel(self.pFilterModel)


    # on model column change, update the model column of the filter and completer as well
    def setModelColumn(self, column):
        self.completer.setCompletionColumn(column)
        self.pFilterModel.setFilterKeyColumn(column)
        super(ExtendedComboBox, self).setModelColumn(column)

class MainWindow(QMainWindow):

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

        self.setGeometry(100, 100, 800, 600)
        self.centerOnScreen()
        self.combo = ExtendedComboBox(self)
        self.my_list = ['','Option 1', 'Option 2', 'Option 3','Option 4', 'Option 5']
        self.combo.addItems(self.my_list)
        Data = {'Option Number': ['Option 2','Option 3','Option 5'],'Color': ['red','blue','grey']}
        df = DataFrame(Data,columns= ['Option Number', 'Color'])

        self.combo.setFixedWidth(250)

        print(df)

        def combo_changed():
            for color in ('red', 'blue', 'grey'):
                try:
                    if color == df.loc[df['Option Number'].str.contains(self.combo.currentText()), 'Color'].iloc[0]:
                        self.combo.setStyleSheet("QComboBox:editable{{ color: {} }}".format(color))
                except IndexError:
                    self.combo.setStyleSheet("QComboBox:editable{{ color: {} }}".format('black'))

        self.combo.currentIndexChanged.connect(combo_changed)

    def centerOnScreen (self):
        resolution = QDesktopWidget().screenGeometry()
        self.move((resolution.width() / 2) - (self.frameSize().width() / 2),
                  (resolution.height() / 2) - (self.frameSize().height() / 2))

if __name__ == '__main__':

    app = QApplication(sys.argv)
    mainWin = MainWindow()
    mainWin.show()
    sys.exit(app.exec_())

PyQt5: Set font color of custom ComboBox text depending on element selected matching another element in a dataframe

1 Answers1