Using QIcon does not display the image

Question

I'm trying to learn PyQt. While going over a tutorial to get the basics I've encountered a problem with QIcon.

The following code is supposed to create a simple window with an icon from an image called 'web.png':

import os
import sys

import PyQt5

dirname = os.path.dirname(PyQt5.__file__)
plugin_path = os.path.join(dirname, 'plugins', 'platforms')
os.environ['QT_QPA_PLATFORM_PLUGIN_PATH'] = plugin_path

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


class Example(QWidget):

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

        self.initUI()


    def initUI(self):

        self.setGeometry(300, 300, 300, 220)
        self.setWindowTitle('Icon')
        self.setWindowIcon(QIcon('web.png'))        

        self.show()


if __name__ == '__main__':

    app = QApplication(sys.argv)
    ex = Example()
    sys.exit(app.exec_())

However, the resulting window contains a standard icon and not the wanted image:

The image web.png is contained within the current working directory. I use Python 3.5.1 and PyQt 5 with Qt 5.6.2.

Any help would be appreciated.

While tinkering about with this, I found that if I try to use an file with an .ico extension, it does work. — Ne_Plus_Ultra
However, the ico quality is rather bad, and I would still like to know if there's a reason to make python read the original files and display them as icons in the top-left corner of the program. Thanks — Ne_Plus_Ultra
Check your imageformats plugins. Seems like you miss them. — ilotXXI

EX7 EX7 · Accepted Answer · 2020-12-30T16:50:07

You should use absolute path instead:

self.setWindowIcon(QIcon('c:/root_to_your_application/web.png'))

or:

import pathlib
current_directory = str(pathlib.Path(__file__).parent.absolute())
path = current_directory + '/web.png'
self.setWindowIcon(QIcon(path))

Using QIcon does not display the image

2 Answers