Qt for Python & PyInstaller#

PyInstaller lets you freeze your python application into a stand-alone executable. This installer supports Linux, macOS, Windows, and more; and is also compatible with 3rd-party Python modules, such as PySide6.

For more details, see the official documentation.

Status of Qt 6 Support#

As of March 2021, Qt 6 is not supported yet. PyInstaller is unable to properly deploy Qt; the Qt plugins are not copied. With that, using --onefile is not possible.

It is possible to use PyInstaller for the non --onefile case though by manually copying the Qt plugins, QML imports and translations into the dist directory after running PyInstaller.

On Windows, this can be achieved by running the windeployqt tool from the Qt SDK on the Qt libraries present in the dist directory, for example:

windeployqt dist\app\Qt6Widgets.dll

Preparation#

Install the PyInstaller via pip with the following command:

pip install pyinstaller

If you’re using a virtual environment, remember to activate it before installing PyInstaller.

After installation, the pyinstaller binary is located in your virtual environment’s bin/ directory, or where your Python executable is located. If that directory isn’t in your PATH, include the whole path when you run pyinstaller.

Warning

If you already have a PySide6 or Shiboken6 version installed in your system path, PyInstaller uses them instead of your virtual environment version.

Freeze an application#

PyInstaller has many options that you can use. To list them all, run pyinstaller -h.

There are two main features:

  • the option to package the whole project (including shared libraries) into one executable file (--onefile)

  • the option to place it in a directory containing the libraries

Additionally, on Windows when the command is running, you can open a console with the -c option (or --console or --nowindowed equivalent).

Otherwise, you can specify to not open such a console window on macOS and Windows with the -w option (or --windowed or --noconsole equivalent).

Create an example#

Now, consider the following script, named hello.py:

import sys
import random
from PySide6.QtWidgets import (QApplication, QLabel, QPushButton,
                               QVBoxLayout, QWidget)
from PySide6.QtCore import Slot, Qt

class MyWidget(QWidget):
    def __init__(self):
        QWidget.__init__(self)

        self.hello = ["Hallo Welt", "你好，世界", "Hei maailma",
            "Hola Mundo", "Привет мир"]

        self.button = QPushButton("Click me!")
        self.text = QLabel("Hello World")
        self.text.setAlignment(Qt.AlignCenter)

        self.layout = QVBoxLayout()
        self.layout.addWidget(self.text)
        self.layout.addWidget(self.button)
        self.setLayout(self.layout)

        # Connecting the signal
        self.button.clicked.connect(self.magic)

    @Slot()
    def magic(self):
        self.text.setText(random.choice(self.hello))

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

    widget = MyWidget()
    widget.resize(800, 600)
    widget.show()

    sys.exit(app.exec())

Since it has a UI, you use the --windowed option.

The command line to proceed looks like this:

pyinstaller --name="MyApplication" --windowed hello.py

This process creates two directories: dist/ and build/. The application executable and the required shared libraries are placed in dist/MyApplication.

To run the application, go to dist/MyApplication and run the program:

cd dist/MyApplication/
./MyApplication

Note

The directory inside dist/ and the executable have the same name.

Use the --onefile option if you prefer to have everything bundled into one executable, without the shared libraries next to it:

pyinstaller --name="MyApplication" --windowed --onefile hello.py

This process takes a bit longer, but in the end you have one executable in the dist/ directory:

cd dist/
./MyApplication

Some Caveats#

PyInstaller Issue#

As mentioned before, if available, PyInstaller picks a system installation of PySide6 or Shiboken6 instead of your virtualenv version without notice. This is negligible if those two versions are the same.

If you’re working with different versions, this can result in frustrating debugging sessions when you think you are testing the latest version, but PyInstaller is working with an older version.

Safety Instructions#

  • When using PyInstaller with virtualenv, make sure that there is no system installation of PySide6 or shiboken6.

  • Before compiling, use pip -uninstall pyside6 pyside6_essentials pyside6_addons shiboken6 -y multiple times, until none of the programs are found anymore.

  • Pip is usually a good tool. But to be 100 % sure, you should directly remove the PySide6 and shiboken6 folders from site-packages.

  • Be sure to use the right version of pip. The safest way to really run the right pip, is to use the Python that you mean: Instead of the pip command, better use:

    <path/to/your/>python -m pip