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Platform

Details about the platform on which the app is running.

Usage

Although Toga is a cross-platform framework, and in theory shouldn't require any special platform-specific handling, in practice you will. If you wish to apply platform-specific modifications to your user interface, or modify business logic on a per-platform basis, you may need to know the currently active backend, or the platform on which your application is running. This can be achieved by using toga.backend and toga.platform.current_platform.

For example:

import toga

if toga.backend == `toga_gtk`:
    # ... perform GTK-specific logic

if toga.platform.current_platform == 'android':
    # ... perform Android-specific business logic

Selecting a specific backend

In general, a Python environment should only have a single Toga backend installed. However, if you need to install multiple backends, you can tell Toga which backend to use by setting the TOGA_BACKEND environment variable to match the name of the Python module for the backend you wish to use (e.g., toga_gtk).

Getting an implementation factory

Developers who want to implement new platform-dependent functionality, or produce a new backend, need a way to access the implementation classes for the current backend. The get_factory function provides a standard way to do this, returning an object whose attributes are lazily-loaded implementation classes.

See the topic guide on Extending Toga for more information.

Reference

toga.backend module-attribute 

backend: str

The name of the backend that is being used by Toga to implement platform-specific capabilities (e.g., toga_cocoa, toga_gtk).

toga.platform.current_platform module-attribute 

current_platform: str

A string identifier of the platform on which the application is currently running. One of:

  • android
  • macOS
  • iOS
  • linux
  • freeBSD
  • web
  • windows

DEPRECATED: This property exists for historical reasons. On Python 3.13 and later, you can use the Python standard library property sys.platform.

It is required on Python 3.12 and earlier because Android historically returned sys.platform == "linux" until the android value was formalied by PEP 783. The names used by current_platform do not exactly match the names returned by sys.platform.

toga.platform.get_factory cached 

get_factory(interface: str | None = None) -> Factory | ModuleType

Return the implementation factory for an interface group.

The object that is returned is a namespace whose attributes are the implementation classes for the current backend contributed by the appropriate entry points.

PARAMETER DESCRIPTION
interface

the name of the interface group for the factory, or None for the default "toga_core" interface. Third-party interface group names should start with "togax_".

TYPE: str | None DEFAULT: None

RETURNS DESCRIPTION
Factory | ModuleType

The factory namespace object.