New Backend - Qt

.github/workflows/ci.yml

@@ -60,6 +60,7 @@ jobs:
         - "demo"
         - "dummy"
         - "gtk"
+        - "qt"
         - "iOS"
         - "toga"
         - "positron"
@@ -247,6 +248,7 @@ jobs:
           briefcase-run-prefix: ""
           briefcase-run-args: ""
           setup-python: true
+          testbed-app: testbed
 
         - backend: "macOS-x86_64"
           platform: "macOS"
@@ -444,7 +446,8 @@ jobs:
       timeout-minutes: 15
       run: |
         ${{ matrix.briefcase-run-prefix }} \
-          briefcase run ${{ matrix.platform }} --log --test ${{ matrix.briefcase-run-args }} -- --ci
+          briefcase run ${{ matrix.platform }} --log --test \
+          ${{ matrix.briefcase-run-args }} --app ${{ matrix.testbed-app }} -- --ci
 
     - name: Upload Logs
       uses: actions/[email protected]

android/tests_backend/widgets/button.py

@@ -21,3 +21,6 @@ def assert_icon_size(self):
             assert (icon.getIntrinsicWidth(), icon.getIntrinsicHeight()) == scaled_size
         else:
             pytest.fail("Icon does not exist")
+
+    def assert_taller_than(self, initial_height):
+        assert self.height > initial_height

changes/1142.feature.rst

@@ -0,0 +1 @@
+Toga now provides a Qt backend for KDE-based desktops.

cocoa/tests_backend/app.py

@@ -25,6 +25,7 @@ class AppProbe(BaseProbe, DialogsMixin):
     supports_key_mod3 = True
     supports_current_window_assignment = True
     supports_dark_mode = True
+    edit_menu_noop_enabled = False
 
     def __init__(self, app):
         super().__init__()

cocoa/tests_backend/widgets/button.py

@@ -56,3 +56,6 @@ def height(self):
             assert self.native.bezelStyle == NSBezelStyle.Rounded
 
         return super().height
+
+    def assert_taller_than(self, initial_height):
+        assert self.height > initial_height

core/src/toga/command.py

@@ -153,6 +153,7 @@ def key(self) -> tuple[tuple[int, int, str], ...]:
     COMMANDS: Group  #: Default group for user-provided commands
     WINDOW: Group  #: Window management commands
     HELP: Group  #: Help commands
+    SETTINGS: Group  #: Preferences menu group for KDE-based apps
 
 
 Group.APP = Group("*", order=-100)
@@ -162,6 +163,7 @@ def key(self) -> tuple[tuple[int, int, str], ...]:
 Group.COMMANDS = Group("Commands", order=30)
 Group.WINDOW = Group("Window", order=90)
 Group.HELP = Group("Help", order=100)
+Group.SETTINGS = Group("Settings", order=80)
 
 
 class ActionHandler(Protocol):

gtk/tests_backend/app.py

@@ -18,6 +18,7 @@ class AppProbe(BaseProbe, DialogsMixin):
     # Gtk 3.24.41 ships with Ubuntu 24.04 where present() works on Wayland
     supports_current_window_assignment = not (IS_WAYLAND and GTK_VERSION < (3, 24, 41))
     supports_dark_mode = True
+    edit_menu_noop_enabled = False
 
     def __init__(self, app):
         super().__init__()

gtk/tests_backend/widgets/button.py

@@ -33,3 +33,6 @@ def background_color(self):
 
     async def press(self):
         self.native.clicked()
+
+    def assert_taller_than(self, initial_height):
+        assert self.height > initial_height

iOS/tests_backend/widgets/button.py

@@ -30,3 +30,6 @@ def color(self):
     @property
     def font(self):
         return self.native.titleLabel.font
+
+    def assert_taller_than(self, initial_height):
+        assert self.height > initial_height

qt/CONTRIBUTING.md

@@ -0,0 +1,11 @@
+# Contributing
+
+BeeWare <3's contributions!
+
+Please be aware that BeeWare operates under a [Code of
+Conduct](https://beeware.org/community/behavior/code-of-conduct/).
+
+If you'd like to contribute to Toga development, our [contribution
+guide](https://toga.readthedocs.io/en/latest/how-to/contribute/index.html) details how
+to set up a development environment, and other requirements we have as part of our
+contribution process.

qt/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2025 Russell Keith-Magee.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+    1. Redistributions of source code must retain the above copyright notice,
+       this list of conditions and the following disclaimer.
+
+    2. Redistributions in binary form must reproduce the above copyright
+       notice, this list of conditions and the following disclaimer in the
+       documentation and/or other materials provided with the distribution.
+
+    3. Neither the name of Toga nor the names of its contributors may
+       be used to endorse or promote products derived from this software without
+       specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

qt/README.rst

@@ -0,0 +1,57 @@
+.. |pyversions| image:: https://img.shields.io/pypi/pyversions/toga-qt.svg
+    :target: https://pypi.python.org/pypi/toga-qt
+    :alt: Python Versions
+
+.. |license| image:: https://img.shields.io/pypi/l/toga-qt.svg
+    :target: https://github.com/beeware/toga-qt/blob/main/LICENSE
+    :alt: BSD-3-Clause License
+
+.. |maturity| image:: https://img.shields.io/pypi/status/toga-qt.svg
+    :target: https://pypi.python.org/pypi/toga-qt
+    :alt: Project status
+
+toga-qt
+========
+
+|pyversions| |license| |maturity|
+
+A Qt backend for the `Toga widget toolkit`_.
+
+This package isn't much use by itself; it needs to be combined with `the core Toga library`_.
+
+For platform requirements, see the Qt platform documentation (TODO).
+
+For more details, see the `Toga project on GitHub`_.
+
+.. _Toga widget toolkit: https://beeware.org/toga
+.. _the core Toga library: https://pypi.python.org/pypi/toga-core
+.. _Toga project on GitHub: https://github.com/beeware/toga
+
+Community
+---------
+
+Toga is part of the `BeeWare suite`_. You can talk to the community through:
+
+* `@[email protected] on Mastodon`_
+* `Discord`_
+* The Toga `GitHub Discussions forum`_
+
+We foster a welcoming and respectful community as described in our
+`BeeWare Community Code of Conduct`_.
+
+.. _BeeWare suite: https://beeware.org
+.. _@[email protected] on Mastodon: https://fosstodon.org/@beeware
+.. _Discord: https://beeware.org/bee/chat/
+.. _GitHub Discussions forum: https://github.com/beeware/toga/discussions
+.. _BeeWare Community Code of Conduct: https://beeware.org/community/behavior/
+
+Contributing
+------------
+
+If you experience problems with Toga, `log them on GitHub
+<https://github.com/beeware/toga/issues>`__.
+
+If you'd like to contribute to Toga development, our `contribution guide
+<https://toga.readthedocs.io/en/latest/how-to/contribute/index.html>`__
+details how to set up a development environment, and other requirements we have
+as part of our contribution process.

qt/pyproject.toml

@@ -0,0 +1,77 @@
+[build-system]
+requires = [
+    "setuptools==80.9.0",
+    "setuptools_scm==9.2.0",
+    "setuptools_dynamic_dependencies==1.0.0",
+]
+build-backend = "setuptools.build_meta"
+
+[project]
+dynamic = ["version", "dependencies"]
+name = "toga-qt"
+description = "An Qt (KDE) backend for the Toga widget toolkit."
+readme = "README.rst"
+requires-python = ">= 3.10"
+license = "BSD-3-Clause"
+license-files = [
+    "LICENSE"
+]
+authors = [
+    {name="John", email="[email protected]"},
+    {name="Russell Keith-Magee", email="[email protected]"},
+]
+maintainers = [
+    {name="BeeWare Team", email="[email protected]"},
+]
+keywords = [
+    "gui",
+    "widget",
+    "cross-platform",
+    "toga",
+    "desktop",
+    "qt",
+]
+classifiers = [
+    "Development Status :: 1 - Planning",
+    "Intended Audience :: Developers",
+    "Operating System :: OS Independent",
+    "Programming Language :: Python :: 3",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: 3.13",
+    "Programming Language :: Python :: 3.14",
+    "Programming Language :: Python :: 3 :: Only",
+    "Topic :: Software Development",
+    "Topic :: Software Development :: User Interfaces",
+    "Topic :: Software Development :: Widget Sets",
+]
+
+
+[project.entry-points."toga.backends"]
+linux = "toga_qt"
+
+[tool.setuptools_scm]
+root = ".."
+
+[tool.setuptools_dynamic_dependencies]
+dependencies = [
+    "qasync",
+    "toga-core == {version}",
+    "system-pyside6 @ git+https://github.com/johnzhou721/system-pyside6.git",
+]
+
+[tool.coverage.run]
+parallel = true
+branch = true
+relative_files = true
+
+# See notes in the root pyproject.toml file.
+source = ["src"]
+source_pkgs = ["toga_qt"]
+
+[tool.coverage.paths]
+source = [
+    "src/toga_qt",
+    "**/toga_qt",
+]

qt/src/toga_qt/__init__.py

@@ -0,0 +1,9 @@
+# Examples of valid version strings
+# __version__ = '1.2.3.dev1'  # Development release 1
+# __version__ = '1.2.3a1'     # Alpha Release 1
+# __version__ = '1.2.3b1'     # Beta Release 1
+# __version__ = '1.2.3rc1'    # RC Release 1
+# __version__ = '1.2.3'       # Final Release
+# __version__ = '1.2.3.post1' # Post Release 1
+
+__version__ = "0.0.0"