Q&A: Are there any built-in QIcons?

In the tutorials on this site and in my books I recommend using the fugue icons set. This is a free set of icons from Yusuke Kamiyamane, a freelance designer from Tokyo. The set contains 3,570 icons and is a great way to add some nice visual touches to your application without much hassle.

But this isn't the only icon set available, and there's another option you may not know about. Read on for details.

Veronica asked:

Are there any built-in icons with PyQt5? I have searched the web and it seems like there are some but I can't find any examples of them being used. Does it depend on the situation? If so, then in which cases can I use an icon without downloading it first?

First we need to clarify what is meant by built in icons -- it can mean two different things depending on context -- either Qt built-in, or system built-in (Linux only). I'll start with the Qt built-ins as that's cross-platform (they're available on Windows, macOS and Linux).

Qt Standard Icons (QStyle StandardPixmap)

Qt ships with a small set of standard icons you can use in any of your applications for common actions. These built-in icons are accessed through the QStyle.StandardPixmap enum and retrieved using style().standardIcon(). They're available on all platforms — Windows, macOS, and Linux — making them a convenient choice when you need common UI icons without bundling external assets.

The following Python script displays all the built-in Qt standard icons in a grid layout:

import sys

from PyQt5.QtWidgets import QApplication, QGridLayout, QPushButton, QStyle, QWidget


class Window(QWidget):
    def __init__(self):
        super().__init__()

        icons = sorted([attr for attr in dir(QStyle) if attr.startswith("SP_")])
        layout = QGridLayout()

        for n, name in enumerate(icons):
            btn = QPushButton(name)

            pixmapi = getattr(QStyle, name)
            icon = self.style().standardIcon(pixmapi)
            btn.setIcon(icon)
            layout.addWidget(btn, n // 4, n % 4)

        self.setLayout(layout)


app = QApplication(sys.argv)

w = Window()
w.show()

app.exec_()

import sys

from PyQt6.QtWidgets import (QApplication, QGridLayout, QPushButton, QStyle,
                             QWidget)


class Window(QWidget):
    def __init__(self):
        super().__init__()

        icons = sorted([attr for attr in dir(QStyle.StandardPixmap) if attr.startswith("SP_")])
        layout = QGridLayout()

        for n, name in enumerate(icons):
            btn = QPushButton(name)

            pixmapi = getattr(QStyle.StandardPixmap, name)
            icon = self.style().standardIcon(pixmapi)
            btn.setIcon(icon)
            layout.addWidget(btn, int(n/4), int(n%4))

        self.setLayout(layout)


app = QApplication(sys.argv)

w = Window()
w.show()

app.exec()

import sys

from PySide2.QtWidgets import QApplication, QGridLayout, QPushButton, QStyle, QWidget


class Window(QWidget):
    def __init__(self):
        super().__init__()

        icons = sorted([attr for attr in dir(QStyle) if attr.startswith("SP_")])
        layout = QGridLayout()

        for n, name in enumerate(icons):
            btn = QPushButton(name)

            pixmapi = getattr(QStyle, name)
            icon = self.style().standardIcon(pixmapi)
            btn.setIcon(icon)
            layout.addWidget(btn, n // 4, n % 4)

        self.setLayout(layout)


app = QApplication(sys.argv)

w = Window()
w.show()

app.exec_()

import sys

from PySide6.QtWidgets import QApplication, QGridLayout, QPushButton, QStyle, QWidget


class Window(QWidget):
    def __init__(self):
        super().__init__()

        icons = sorted(
            [attr for attr in dir(QStyle.StandardPixmap) if attr.startswith("SP_")]
        )
        layout = QGridLayout()

        for n, name in enumerate(icons):
            btn = QPushButton(name)

            pixmapi = getattr(QStyle, name)
            icon = self.style().standardIcon(pixmapi)
            btn.setIcon(icon)
            layout.addWidget(btn, n // 4, n % 4)

        self.setLayout(layout)


app = QApplication(sys.argv)

w = Window()
w.show()

app.exec()

If you run this script you'll see the following window, listing all the available icons.

Qt's Built-in Icons — all QStyle.StandardPixmap icons shown with their names

Complete List of Qt Built-in Standard Icons (QStyle.StandardPixmap)

The full table of all QStyle.StandardPixmap icon names is below. You can use any of these in PyQt5, PyQt6, PySide2, or PySide6 applications.

How to Use a Specific Built-in QIcon in Your Application

In our script above to get the icons we're looking them up by name on the QStyle object, using getattr -- but this is only necessary so we can iterate over the list of names and display the icon next to their name. If you want a specific icon you can access it directly. For example, to use the critical message box icon:

pixmapi = QStyle.SP_MessageBoxCritical
icon = self.style().standardIcon(pixmapi)

pixmapi = QStyle.StandardPixmap.SP_MessageBoxCritical
icon = self.style().standardIcon(pixmapi)

In PyQt6 the flags must be accessed via QStyle.StandardPixmap. In other versions, they are available on QStyle itself.

Once you have the QIcon object, you can use it anywhere Qt expects an icon — on buttons, toolbars, menus, window titles, and more.

Free Desktop Theme Icons (Linux)

On Linux desktops there is something called the Free Desktop Specification which defines standard names for icons for specific actions.

If your application uses these specific icon names (and loads the icon from a "theme") then on Linux your application will use the current icon set which is enabled on the desktop. The idea is to make all applications have the same look & feel while remaining user configurable.

Setting Theme Icons in Qt Designer

To use these icons within Qt Designer you would select the drop-down and choose "Set Icon From Theme..."

You then enter the name of the icon you want to use, e.g. document-new (the full list of valid names).

Setting Theme Icons in Python Code with QIcon.fromTheme()

If you're not using designer, you can set icons from a theme in your code using QIcon.fromTheme():

        icon = QtGui.QIcon.fromTheme("document-new")
        self.pushButton_n6.setIcon(icon)

If you're developing a cross-platform application you'll still need your own icons for Windows & macOS, but by using these theme names you can ensure that your app looks native when run on Linux.

Does the QIcon.fromTheme() option only work on Linux?

Qt themes work on all platforms, it's just that on Linux you get the theme for free. On non-Linux platforms you have to define your own icon theme from scratch. However, this is only really worth doing if you want to have a Linux-native look, for other use cases the QResource system is simpler.