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 PySide2.

For more details, see the official documentation.

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 PySide2 or Shiboken2 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 PySide2.QtWidgets import (QApplication, QLabel, QPushButton,
                               QVBoxLayout, QWidget)
from PySide2.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 PySide2 or Shiboken2 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.

Issue with numpy in Python 2.7.16

A recent issue with PyInstaller is the appearance of Python 2.7.16. This Python version creates an issue that is known from Python 3 as a Tcl/Tk problem. This rarely shows up in Python 3 because Tcl/Tk is seldom used with PyInstaller.

On Python 2.7.16, this problem is common, as many developers use numpy. For some reason, installing numpy creates a dependency to Tcl/Tk, which can be circumvented only by explicitly excluding Tcl/Tk by adding this line to spec-file’s analysis section:

excludes=['FixTk', 'tcl', 'tk', '_tkinter', 'tkinter', 'Tkinter'],

Safety Instructions

  • When using PyInstaller with virtualenv, make sure that there is no system installation of PySide2 or shiboken2.

  • Before compiling, use pip -uninstall pyside2 shiboken2 -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 PySide2 and shiboken2 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