wxPython

What Is wxPython?

wxPython is a set of Python bindings for the C++ wxWidgets library. Unlike Qt or Kivy, which draw their own widgets, wxWidgets maps each control to the host operating system's native API — Win32/UWP on Windows, Cocoa on macOS, GTK on Linux. The result: your app genuinely looks and behaves like a native application on each platform.

wxPython has been around since 1998 and powers many long-lived desktop tools. Its API is more verbose than tkinter but offers significantly richer widgets and better platform integration (system tray, native file dialogs, accessibility).

Architecture & Core Concepts

• wx.App — application object; call MainLoop() to start.
• wx.Frame — top-level window; contains panels and controls.
• wx.Panel — container inside a frame; groups related controls.
• Sizers — BoxSizer, GridSizer, FlexGridSizer handle layout (similar to Qt layouts).
• Event binding — widget.Bind(wx.EVT_BUTTON, handler) connects events to functions.
• wxPython Phoenix — the modern Python 3 branch; always use Phoenix (wx 4.x).

Common widgets

Installation

pip install wxPython

# Verify:
python -c "import wx; print(wx.version())"

# Demo apps ship with wx:
python -m wx.lib.inspection

Example 1 — Button with message box

import wx

app = wx.App()
frame = wx.Frame(None, title="wxPython demo", size=(300, 160))
panel = wx.Panel(frame)
btn = wx.Button(panel, label="Say hi", pos=(20, 20))
btn.Bind(wx.EVT_BUTTON, lambda e: wx.MessageBox("Hello!"))
frame.Show()
app.MainLoop()

Example 2 — Form with sizers (recommended layout)

import wx

class FormFrame(wx.Frame):
    def __init__(self):
        super().__init__(None, title="Contact", size=(360, 200))
        panel = wx.Panel(self)
        grid = wx.FlexGridSizer(3, 2, 8, 8)
        self.name  = wx.TextCtrl(panel)
        self.email = wx.TextCtrl(panel)
        grid.AddMany([(wx.StaticText(panel, label="Name:"),  0), (self.name,  1, wx.EXPAND),
                      (wx.StaticText(panel, label="Email:"), 0), (self.email, 1, wx.EXPAND)])
        grid.AddGrowableCol(1)
        btn = wx.Button(panel, label="Save")
        btn.Bind(wx.EVT_BUTTON, self.on_save)
        sizer = wx.BoxSizer(wx.VERTICAL)
        sizer.Add(grid, 1, wx.ALL | wx.EXPAND, 12)
        sizer.Add(btn, 0, wx.ALIGN_RIGHT | wx.ALL, 12)
        panel.SetSizer(sizer)
    def on_save(self, event):
        wx.MessageBox(f"{self.name.GetValue()} / {self.email.GetValue()}")

app = wx.App()
FormFrame().Show()
app.MainLoop()

Example 3 — Tabbed notebook

import wx

app = wx.App()
frame = wx.Frame(None, title="Tabs")
nb = wx.Notebook(frame)
page1 = wx.Panel(nb)
page2 = wx.Panel(nb)
nb.AddPage(page1, "Settings")
nb.AddPage(page2, "About")
wx.StaticText(page1, label="Configure here", pos=(20, 20))
frame.Show()
app.MainLoop()

Practical advice

• Always use sizers instead of absolute pos= coordinates for resizable layouts.
• Subclass wx.Frame or wx.Panel for reusable UI components.
• Use wx.CallAfter() to update the UI from background threads safely.
• wx.glcanvas and wx.lib provide OpenGL and extended widgets.
• wxPython apps bundle cleanly with PyInstaller; wx is auto-detected on most platforms.

Real-world use cases

• Desktop apps where native OS appearance is mandatory
• Cross-platform tools for Windows and macOS users
• Scientific and engineering utilities
• Replacement for legacy wxWidgets C++ apps with Python scripting