New Backend - Qt

.github/dependabot.yml

@@ -73,6 +73,14 @@ updates:
       day: "sunday"
       time: "20:00"
 
+  - package-ecosystem: "pip"
+    directory: "/qt"
+    schedule:
+      # Check for updates on Sunday, 8PM UTC
+      interval: "weekly"
+      day: "sunday"
+      time: "20:00"
+
   - package-ecosystem: "pip"
     directory: "/testbed"
     ignore:

.github/workflows/ci.yml

@@ -56,6 +56,7 @@ jobs:
         - "demo"
         - "dummy"
         - "gtk"
+        - "qt"
         - "iOS"
         - "toga"
         - "positron"
@@ -208,7 +209,7 @@ jobs:
         tox -e trav-compat
 
   testbed:
-    name: Testbed
+    name: Testbed (${{ matrix.backend }})
     needs: [ package, core-and-travertino ]
     runs-on: ${{ matrix.runs-on }}
     strategy:
@@ -231,6 +232,7 @@ jobs:
           briefcase-run-prefix: ""
           briefcase-run-args: ""
           setup-python: true
+          testbed-app: "testbed"
 
         - backend: "macOS-x86_64"
           platform: "macOS"
@@ -277,7 +279,7 @@ jobs:
         - backend: "linux-wayland-gtk3"
           platform: "linux"
           runs-on: "ubuntu-24.04"
-          # The package list should be the same as in unix-prerequisites.rst, and the BeeWare
+          # The package list should be the same as in unix-prerequisites.md, and the BeeWare
           # tutorial, plus mutter to provide a window manager.
           pre-command: |
             sudo apt update -y
@@ -306,7 +308,7 @@ jobs:
           runs-on: "ubuntu-24.04"
           env:
             XDG_RUNTIME_DIR: "/tmp"
-          # The package list should be build on the same base as unix-prerequisites.rst,
+          # The package list should be build on the same base as unix-prerequisites.md,
           # and the BeeWare tutorial. Additional packages will be added for window
           # management, and features such as web views and geolocation that aren't part
           # of the default/tutorial environment.
@@ -333,6 +335,70 @@ jobs:
           setup-python: false  # Use the system Python packages
           app-user-data-path: "$HOME/.local/share/testbed"
 
+        - backend: "linux-x11-qt"
+          platform: "linux"
+          runs-on: "ubuntu-24.04"
+          testbed-app: "testbed-qt"
+          # The package list should be dependencies listed in unix-prerequsites.md, plus we need a window
+          # manager that is reasonably lightweight, honors full screen mode, and
+          # treats the window position as the top-left corner of the *window*, not the
+          # top-left corner of the window *content*. The default GNOME window managers of
+          # most distros meet these requirements, but they're heavyweight; flwm doesn't
+          # work either. Blackbox is the lightest WM we've found that works.
+          # PySide6 must be installed in VM to test that system-pyside6 works properly.
+          pre-command: |
+            sudo apt update -y
+            sudo apt install -y --no-install-recommends \
+              blackbox python3-dev xvfb \
+              gnome-session-canberra build-essential \
+              libfontconfig1-dev libfreetype-dev libgtk-3-dev \
+              libx11-dev libx11-xcb-dev libxext-dev \
+              libxfixes-dev libxi-dev libxkbcommon-dev \
+              libxkbcommon-x11-dev libxrender-dev 'libxcb*-dev' \
+
+            # Start Virtual X Server
+            echo "Start X server..."
+            Xvfb :99 -screen 0 2048x1536x24 &
+            sleep 1
+
+            # Start Window Mmanager
+            echo "Start window manager..."
+            DISPLAY=:99 blackbox &
+            sleep 1
+          briefcase-run-prefix: 'DISPLAY=:99'
+          setup-python: false  # Use the system Python packages
+          app-user-data-path: "$HOME/.local/share/testbed"
+
+        - backend: "linux-wayland-qt"
+          platform: "linux"
+          runs-on: "ubuntu-24.04"
+          testbed-app: "testbed-qt"
+          # The package list should be unix-prerequisites.md, plus mutter to provide a window
+          # manager.
+          pre-command: |
+            sudo apt update -y
+            sudo apt install -y --no-install-recommends \
+              mutter python3-dev xvfb \
+              gnome-session-canberra \
+              libwayland-dev libwayland-egl1-mesa libwayland-server0 \
+              libgles2-mesa-dev libxkbcommon-dev
+
+            # Start Virtual X Server
+            echo "Start X server..."
+            Xvfb :99 -screen 0 2048x1536x24 &
+            sleep 1
+
+            # Start Window Manager
+            echo "Start window manager..."
+            # mutter is being run inside a virtual X server because mutter's headless
+            # mode does not provide a Gdk.Display
+            DISPLAY=:99 MUTTER_DEBUG_DUMMY_MODE_SPECS=2048x1536 \
+              mutter --nested --wayland --no-x11 --wayland-display toga &
+            sleep 1
+          briefcase-run-prefix: "WAYLAND_DISPLAY=toga"
+          setup-python: false  # Use the system Python packages
+          app-user-data-path: "$HOME/.local/share/testbed"
+
         - backend: "textual-linux"
           platform: "linux"
           runs-on: "ubuntu-latest"
@@ -428,7 +494,8 @@ 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]

.github/workflows/publish.yml

@@ -25,6 +25,7 @@ jobs:
         - "toga_demo"
         - "toga_dummy"
         - "toga_gtk"
+        - "toga_qt"
         - "toga_positron"
         - "toga_textual"
         - "toga_ios"

.github/workflows/release.yml

@@ -68,6 +68,7 @@ jobs:
         - "toga_demo"
         - "toga_dummy"
         - "toga_gtk"
+        - "toga_qt"
         - "toga_ios"
         - "toga_positron"
         - "toga_textual"

android/tests_backend/app.py

@@ -14,6 +14,7 @@
 class AppProbe(BaseProbe, DialogsMixin):
     supports_key = False
     supports_dark_mode = True
+    edit_menu_noop_enabled = False
 
     def __init__(self, app):
         super().__init__(app)

changes/1142.feature.md

@@ -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__()

core/src/toga/command.py

@@ -160,6 +160,8 @@ def key(self) -> tuple[tuple[int, int, str], ...]:
     """Window management commands"""
     HELP: Group
     """Help commands"""
+    SETTINGS: Group
+    """Preferences commands (used only for Qt backend by default)"""
 
 
 Group.APP = Group("*", order=-100)
@@ -169,6 +171,7 @@ 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):

docs/config.yml

@@ -4,7 +4,8 @@ not_in_nav: |
   /index.md
   reference/api/widgets/table-values.md
   reference/api/widgets/table-accessors.md
-  reference/platforms/unix-prerequisites.md
+  reference/platforms/linux/gtk-prerequisites.md
+  reference/platforms/linux/qt-prerequisites.md
 
 validation:
   omitted_files: warn

docs/en/SUMMARY.md

@@ -53,7 +53,9 @@
     - [Supported Platforms](reference/platforms/index.md)
         - [macOS](./reference/platforms/macOS.md)
         - [Windows](./reference/platforms/windows.md)
-        - [Linux/Unix](./reference/platforms/linux.md)
+        - [Linux](./reference/platforms/linux/index.md)
+            - [GTK](./reference/platforms/linux/gtk.md)
+            - [Qt](./reference/platforms/linux/qt.md)
         - [Android](./reference/platforms/android.md)
         - [iOS](./reference/platforms/iOS.md)
         - [Web](./reference/platforms/web.md)

docs/en/how-to/contribute/code.md

@@ -14,7 +14,7 @@ View the [macOS prerequisites][macos-prerequisites].
 
 /// tab | Linux
 
-View the [Linux prerequisites][linux-prerequisites].
+View the [GTK prerequisites][gtk-prerequisites] or the [Qt prerequisites][qt-prerequisites].
 
 ///
 
@@ -735,24 +735,34 @@ The above test suites exercise `toga-core` and `travertino` - but what about the
 
 ### Running the testbed app
 
-To run the testbed app, install [Briefcase](https://briefcase.readthedocs.io/en/latest/), and run the app in developer test mode:
+To run the testbed app, install [Briefcase](https://briefcase.readthedocs.io/en/latest/), and run the app in developer test mode as described below.  Note that you should have only 1 backend -- the backend that you're planning to test -- installed in your virtual environment when running the test suite in developer mode.
 
 /// tab | macOS
 
 ```console
 (.venv) $ python -m pip install briefcase
 (.venv) $ cd testbed
-(.venv) $ briefcase dev --test
+(.venv) $ briefcase dev --app testbed --test
 ```
 
 ///
 
 /// tab | Linux
 
+For testing the GTK backend:
+
 ```console
 (.venv) $ python -m pip install briefcase
 (.venv) $ cd testbed
-(.venv) $ briefcase dev --test
+(.venv) $ briefcase dev --app testbed --test
+```
+
+For testing the Qt backend:
+
+```console
+(.venv) $ python -m pip install briefcase
+(.venv) $ cd testbed
+(.venv) $ briefcase dev --app testbed-qt --test
 ```
 
 ///
@@ -762,7 +772,7 @@ To run the testbed app, install [Briefcase](https://briefcase.readthedocs.io/en/
 ```doscon
 (.venv) C:\...>python -m pip install briefcase
 (.venv) C:\...>cd testbed
-(.venv) C:\...>briefcase dev --test
+(.venv) C:\...>briefcase dev --app testbed --test
 ```
 
 ///
@@ -780,30 +790,36 @@ So - to run *only* the button tests in slow mode, you could run:
 /// tab | macOS
 
 ```console
-(.venv) $ briefcase dev --test -- tests/widgets/test_button.py --slow
+(.venv) $ briefcase dev --app testbed --test -- tests/widgets/test_button.py --slow
 ```
 
 ///
 
 /// tab | Linux
 
 ```console
-(.venv) $ briefcase dev --test -- tests/widgets/test_button.py --slow
+(.venv) $ briefcase dev --app testbed --test -- tests/widgets/test_button.py --slow
+```
+
+or
+
+```console
+(.venv) $ briefcase dev --app testbed-qt --test -- tests/widgets/test_button.py --slow
 ```
 
 ///
 
 /// tab | Windows
 
 ```doscon
-(.venv) C:\...>briefcase dev --test -- tests/widgets/test_button.py --slow
+(.venv) C:\...>briefcase dev --app testbed --test -- tests/widgets/test_button.py --slow
 ```
 
 ///
 
 This test will take a lot longer to run, but you'll see the widget (Button, in this case) go through various color, format, and size changes as the test runs. You won't get a coverage report if you run a subset of the tests, or if you enable slow mode.
 
-### Running testbed in developer mode
+### Running the testbed for mobile platforms
 
 Developer mode is useful for testing desktop platforms (Cocoa, Winforms and GTK); but if you want to test a mobile backend, you'll need to use `briefcase run`.
 
@@ -812,13 +828,13 @@ Developer mode is useful for testing desktop platforms (Cocoa, Winforms and GTK)
 To run the Android test suite:
 
 ```console
-(.venv) $ briefcase run android --test
+(.venv) $ briefcase run android --app testbed --test
 ```
 
 To run the iOS test suite:
 
 ```console
-(.venv) $ briefcase run iOS --test
+(.venv) $ briefcase run iOS --app testbed --test
 ```
 
 ///
@@ -828,7 +844,7 @@ To run the iOS test suite:
 To run the Android test suite:
 
 ```console
-(.venv) $ briefcase run android --test
+(.venv) $ briefcase run android --app testbed --test
 ```
 
 iOS tests can't be executed on Linux.
@@ -840,7 +856,7 @@ iOS tests can't be executed on Linux.
 To run the Android test suite:
 
 ```doscon
-(.venv) C:\...>briefcase run android --test
+(.venv) C:\...>briefcase run android --app testbed --test
 ```
 
 iOS tests can't be executed on Windows.

docs/en/index.md

@@ -2,7 +2,7 @@
 
 Toga is a Python native, OS native, cross-platform GUI toolkit. Toga consists of a library of base components with a shared interface to simplify platform-agnostic GUI development.
 
-Toga is available on macOS, Windows, Linux (GTK), Android, iOS, for single-page web apps, and console apps.
+Toga is available on macOS, Windows, Linux (GTK or Qt), Android, iOS, for single-page web apps, and console apps.
 
 /// tab | macOS
 
@@ -16,7 +16,7 @@ Toga is available on macOS, Windows, Linux (GTK), Android, iOS, for single-page
 
 ///
 
-/// tab | Linux
+/// tab | Linux (GTK)
 
 ![/images/toga-demo-gtk.png](/images/toga-demo-gtk.png){ width="450" }