desktop-app 0.5.0

OS menu shortcuts, correct taskbar behaviour, and environment activation for Python GUI apps

desktop-app

desktop-app simplifies making a Python GUI application install, launch, and behave in a standard way with respect to the application menus and the taskbar in Windows and Linux, and as a native application bundle on macOS.

If your application is a Python module runnable from the command line as python -m mymodule, then with minimal configuration desktop-app can:

• Create a launcher script (or .exe on windows) that runs your application
  • after activating a conda env or virtual environment, if any
  • with a hidden console if on Windows
• Install a start menu shortcut (Windows), .desktop file (Linux), or .app bundle (macOS) to launch your application from your desktop applications menu
• Ensure your application appears in the taskbar with the correct name and icon, and can be pinned correctly.

Basic Usage

Here we'll follow the example in this repository for a module called oink, developed by Old MacDonald's Farm. Before Old MacDonald had heard of desktop-app, he had a package that looked like this:

.
├── oink
│   ├── __init__.py
│   └── __main__.py
└── setup.py

Where setup.py is:

from setuptools import setup

setup(
    name='oink',
    version='1.0',
    author='Old MacDonald',
    author_email="[e-mail]",
    url='http://eie.io',
    packages=["oink"],
    setup_requires=['setuptools'],
)

__main__.py is:

import tkinter

root = tkinter.Tk()
root.geometry("300x300")
w = tkinter.Label(root, text="Oink!")
w.place(relx=0.5, rely=0.5, anchor=tkinter.CENTER)
root.mainloop()

And __init__.py is empty.

After installing this package somewhere, MacDonald can run it from a terminal with python -m oink, and it shows a little window

[README still in progress!]

Reasons

Why a hidden console on Windows?

The usual recommendation to run Python GUI applications is with Pythonw.exe, which does not create a console window. However, when running under Pythonw.exe, a simple print() call will raise an exception, and certain low-level output redirection of subprocesses does not work due to the stdout and stderr filehandles not existing. Furthermore, some tools may create subprocesses that call cmd.exe, or Python.exe, briefly popping up console windows of their own since one doesn't already exist.

In order to be able to ignore these problems and code the same as you would with a console, in Windows the launcher script runs your application in a subprocess using Python.exe, but with the CREATE_NO_WINDOW flag so that the console exists, but is not visible.

Why activate environments?

Activating environments is not strictly necessary except when using conda on Windows, in which case some compiled extensions (notably, Qt libraries) cannot be imported unless the environment is active.

However, even on other platforms activating the environment simplifies running other programs that might be installed to the bin/Scripts directory of the virtual environment - calling code would otherwise have to manually find this directory and provide the full path to the programs it wants to run.