Turn Any Python Function into a GUI

What if you could get a GUI without writing GUI code?

The community already has two well-known answers: PyGUIAdapter and Gooey.

• PyGUIAdapter

  

  

• Gooey

  

  

And when a terminal UI is enough, Trogon is a library I personally like a lot.

Now there is a new challenger: ArgSense.

So what is different?

ArgSense is a command line argument parser at heart. The GUI is a recent, optional layer on top of it. The pitch:

• Your function does not change. ArgSense reads its signature and annotations and builds the interface from them: every parameter becomes a widget.
• It stays light. Compared with Gooey, the UI is a motorcycle next to a car: fewer knobs, much less to learn.
• It can produce a desktop launcher. A double-clickable .exe or .lnk, with an icon of your own.
• The launcher is tiny. A .lnk is 1–2 KB; an .exe is about 1.2 MB. It does not bundle a Python runtime — it starts the venv you already have. A PyInstaller or PySide build of the same script weighs tens or hundreds of megabytes.

• It does not build on argparse. The parser is ArgSense's own, and that is the library's main business.

  Before (argparse + gooey):
  

  from gooey import Gooey, GooeyParser
  
  @Gooey(program_name='Image Resizer')
  def main():
      parser = GooeyParser(description='Resize images in a folder.')
      parser.add_argument(
          'src', metavar='Source folder', widget='DirChooser'
      )
      parser.add_argument(
          '--width', type=int, default=800, metavar='Target width'
      )
      parser.add_argument(
          '--overwrite',
          action='store_true',
          metavar='Overwrite originals',
      )
      args = parser.parse_args()
      print(args)
  
  if __name__ == '__main__':
      main()
  

  After (argsense):
  

  from argsense import cli
  
  def resize(src: str, width: int = 800, overwrite: bool = False):
      """
      Resize images in a folder.
  
      params:
          src: the folder of images.
          width: the target width in pixels.
          overwrite: replace the originals instead of writing copies.
      """
      print(f'resizing {src} to {width}px ...')
  
  if __name__ == '__main__':
      # python main.py :gui
      cli.run(resize)
  

• No PySide, PyQt or wxPython. The form is rendered by streamlit-canary, and the native window is opened by pyapp-window.

Install

pip install argsense[all]

That installs ArgSense plus what the GUI needs: pillow (to turn a PNG icon into an ICO), streamlit-canary (the form), pyapp-window (the window), and a few more.

One more thing, if you want the desktop launcher: two binaries are deliberately not shipped in the wheel.

python -m argsense pull-launcher-misc

It fetches rcedit.exe (~1.3 MB) and stub.exe (~1.2 MB)¹ from the repository's misc folder into <argsense>/launcher/assets/.

Use

One function

# main.py
from argsense import cli


def resize(src: str, width: int = 800, overwrite: bool = False):
    """
    Resize images in a folder.

    params:
        src: the folder of images.
        width: the target width in pixels.
        overwrite: replace the originals instead of writing copies.
    """
    print(f'resizing {src} to {width}px (overwrite={overwrite})')


if __name__ == '__main__':
    cli.run(resize)

First of all it is a command line tool:

python main.py --help
python main.py ./photos --width 1280

Append :gui, and the same function becomes a window:

python main.py :gui     # a native window
python main.py :guiw    # a browser tab (w = windowless, like "pythonw")
python main.py ./photos --width 1280 :gui  # prefill args into components

A desktop launcher

python -m argsense create_launcher

python -m argsense create_launcher main.py "Image Resizer" -a "./photos --width 1280"

• The output goes to the desktop by default: Image Resizer.exe when the toolchain is in place, otherwise Image Resizer.lnk. Pass -o <dir> to write it elsewhere; a shortcut is then left on the desktop.
• -a bakes arguments into the launcher, so the form is prefilled on double-click.
• -i logo.png sets the icon for both the launcher and the window (a PNG is converted to a multi-size ICO).
• -t / -z set the window title and size; -p pins the port (the default is a free port, picked at every start).
• -c keeps a console window around, for debugging.
• A module works as well: create_launcher myapp.main -n MyApp is the equivalent of python -m myapp.main :gui.

One caveat: the launcher does not bundle a Python runtime. It records the interpreter of the venv you built it from, which makes it perfect for your own machine and useless on a machine without your environment.

Who is it for

• Tools you build for yourself, where remembering a dozen flags is the annoying part.
• Command line scripts with a lot of parameters.
• Machines where you set the environment up but the person using it does not live in a terminal — hand them a desktop launcher instead.

Not for: polished desktop apps that need custom widgets and hand-made layouts. Those still belong to Qt, or to a web front end.

Try it

pip install argsense[all]
python -m argsense pull-launcher-misc
python -m argsense welcome gui

welcome also takes cli and tui, if you want to see the other two faces of the same demo.

• Repository: https://github.com/likianta/argsense-cli
• PyPI: https://pypi.org/project/argsense/

If you have ever put off building an interface for a script, try :gui first — it costs one token.

1. If GitHub is slow or blocked where you are, use the mirror: python -m argsense pull-launcher-misc --mirror-site. ↩