Added set_fullscreen API to WindowAdapter.

See #3283

Cargo.toml

@@ -29,6 +29,7 @@ members = [
     'examples/energy-monitor',
     'examples/mcu-board-support',
     'examples/uefi-demo',
+    'examples/fullscreen_toggle',
     'helper_crates/const-field-offset',
     'helper_crates/vtable',
     'helper_crates/vtable/macro',

docker/Dockerfile.torizon-demos

@@ -53,6 +53,5 @@ RUN apt-get update \
 
 COPY --from=build /slint/demos/* /usr/bin/
 
-ENV SLINT_FULLSCREEN=1
 ENV SLINT_BACKEND=winit-skia
 CMD /usr/bin/printerdemo

docs/reference/src/advanced/backend_qt.md

@@ -10,10 +10,3 @@ macOS, Windows, Linux with Wayland and X11, and direct full-screen rendering via
 The Qt backend only supports software rendering at the moment. That means it runs with any graphics driver,
 but it does not utilize GPU hardware acceleration.
 
-## Configuration Options
-
-The Qt backend reads and interprets the following environment variables:
-
-| Name               | Accepted Values | Description                                                        |
-|--------------------|-----------------|--------------------------------------------------------------------|
-| `SLINT_FULLSCREEN` | any value       | If this variable is set, every window is shown in fullscreen mode. |

docs/reference/src/advanced/backend_winit.md

@@ -17,11 +17,3 @@ The Winit backend supports different renderers. They can be explicitly selected
 | Skia Software | Software-only rendering with Skia           | `winit-skia-software`                    |
 | software      | Software-rendering, no GPU required         | `winit-software`                         |
 
-
-## Configuration Options
-
-The Winit backend reads and interprets the following environment variables:
-
-| Name               | Accepted Values | Description                                                        |
-|--------------------|-----------------|--------------------------------------------------------------------|
-| `SLINT_FULLSCREEN` | any value       | If this variable is set, every window is shown in fullscreen mode. |

examples/fullscreen_toggle/CMakeLists.txt

@@ -0,0 +1,13 @@
+# Copyright © SixtyFPS GmbH <info@slint.dev>
+# SPDX-License-Identifier: MIT
+
+cmake_minimum_required(VERSION 3.21)
+project(fullscreen_toggle LANGUAGES CXX)
+
+if (NOT TARGET Slint::Slint)
+    find_package(Slint REQUIRED)
+endif()
+
+add_executable(fullscreen_toggle fullscreen_toggle.cpp)
+target_link_libraries(fullscreen_toggle PRIVATE Slint::Slint)
+slint_target_sources(fullscreen_toggle fullscreen_toggle.slint)

examples/fullscreen_toggle/Cargo.toml

@@ -0,0 +1,21 @@
+# Copyright © SixtyFPS GmbH <info@slint.dev>
+# SPDX-License-Identifier: MIT
+
+[package]
+name = "fullscreen_toggle"
+version = "1.4.0"
+authors = ["Slint Developers <info@slint.dev>"]
+edition = "2021"
+publish = false
+license = "MIT"
+
+[[bin]]
+path = "main.rs"
+name = "fullscreen_toggle"
+
+[dependencies]
+slint = { path = "../../api/rs/slint" }
+
+[build-dependencies]
+slint-build = { path = "../../api/rs/build" }
+

examples/fullscreen_toggle/fullscreen_toggle.cpp

@@ -0,0 +1,18 @@
+// Copyright © SixtyFPS GmbH <info@slint.dev>
+// SPDX-License-Identifier: MIT
+
+#include "fullscreen_toggle.h"
+#include <random>
+
+int main()
+{
+  auto app_window = AppWindow::create();
+  bool fullscreen = false;
+  app_window.on_fullscreen_toggle([fullscreen, main_window_weak = slint::ComponentWeakHandle(main_window)] {
+      auto main_window = *main_window_weak.lock();
+      fullscreen = !fullscreen;
+      main_window.window().set_fullscreen(fullscreen);
+      });
+
+  main_window->run();
+}

examples/fullscreen_toggle/fullscreen_toggle.slint

@@ -0,0 +1,20 @@
+// Copyright © SixtyFPS GmbH <info@slint.dev>
+// SPDX-License-Identifier: MIT
+
+import { Button, VerticalBox } from "std-widgets.slint";
+
+export component AppWindow inherits Window {
+    callback fullscreen-toggle();
+    VerticalBox {
+        Text {
+            text: "Toggle Button";
+        }
+        Button {
+            text: "Toggle fullscreen";
+            clicked => {
+                root.fullscreen-toggle();
+            }
+        }
+    }
+}
+

examples/fullscreen_toggle/main.rs

@@ -0,0 +1,20 @@
+// Copyright © SixtyFPS GmbH <info@slint.dev>
+// SPDX-License-Identifier: MIT
+
+slint::slint! {
+    import { AppWindow } from "fullscreen_toggle.slint";
+}
+
+fn main() -> Result<(), slint::PlatformError> {
+    let ui = AppWindow::new()?;
+    let mut fullscreen = false;
+
+    let ui_handle = ui.as_weak();
+    ui.on_fullscreen_toggle(move || {
+        let ui = ui_handle.unwrap();
+        fullscreen = !fullscreen;
+        ui.window().set_fullscreen(fullscreen);
+    });
+
+    ui.run()
+}

internal/backends/qt/qt_window.rs

@@ -1530,11 +1530,7 @@ impl WindowAdapter for QtWindow {
     fn set_visible(&self, visible: bool) -> Result<(), PlatformError> {
         if visible {
             let widget_ptr = self.widget_ptr();
-            let fullscreen = std::env::var("SLINT_FULLSCREEN").is_ok();
-            cpp! {unsafe [widget_ptr as "QWidget*", fullscreen as "bool"] {
-                if (fullscreen) {
-                    widget_ptr->setWindowState(Qt::WindowFullScreen);
-                }
+            cpp! {unsafe [widget_ptr as "QWidget*"] {
                 widget_ptr->show();
             }};
             let qt_platform_name = cpp! {unsafe [] -> qttypes::QString as "QString" {
@@ -1702,6 +1698,18 @@ impl WindowAdapter for QtWindow {
         }};
     }
 
+    fn set_fullscreen(&self, fullscreen: bool) {
+        let widget_ptr = self.widget_ptr();
+        cpp! {unsafe [widget_ptr as "QWidget*", fullscreen as "bool"] {
+                if (fullscreen) {
+                    widget_ptr->setWindowState(Qt::WindowFullScreen);
+                } else {
+                    widget_ptr->setWindowState(Qt::WindowNoState);
+                }
+            }
+        };
+    }
+
     fn internal(&self, _: i_slint_core::InternalToken) -> Option<&dyn WindowAdapterInternal> {
         Some(self)
     }

internal/backends/winit/winitwindowadapter.rs

@@ -203,11 +203,6 @@ impl WinitWindowAdapter {
         let mut window_builder =
             winit::window::WindowBuilder::new().with_transparent(true).with_visible(false);
 
-        if std::env::var("SLINT_FULLSCREEN").is_ok() {
-            window_builder =
-                window_builder.with_fullscreen(Some(winit::window::Fullscreen::Borderless(None)));
-        }
-
         window_builder = window_builder.with_title("Slint Window".to_string());
 
         #[cfg(target_arch = "wasm32")]
@@ -579,6 +574,14 @@ impl WindowAdapter for WinitWindowAdapter {
         });
     }
 
+    fn set_fullscreen(&self, fullscreen: bool) {
+        if fullscreen {
+            self.winit_window.set_fullscreen(Some(winit::window::Fullscreen::Borderless(None)));
+        } else {
+            self.winit_window.set_fullscreen(None);
+        }
+    }
+
     fn internal(&self, _: corelib::InternalToken) -> Option<&dyn WindowAdapterInternal> {
         Some(self)
     }

internal/core/api.rs

@@ -446,6 +446,11 @@ impl Window {
         crate::window::WindowAdapter::set_size(&*self.0.window_adapter(), size);
     }
 
+    /// Set or unset the window to display fullscreen.
+    pub fn set_fullscreen(&self, fullscreen: bool) {
+        self.0.window_adapter().set_fullscreen(fullscreen);
+    }
+
     /// Dispatch a window event to the scene.
     ///
     /// Use this when you're implementing your own backend and want to forward user input events.

internal/core/window.rs

@@ -132,6 +132,9 @@ pub trait WindowAdapter {
     /// be called again.
     fn update_window_properties(&self, _properties: WindowProperties<'_>) {}
 
+    /// Set to display the window as fullscreen.
+    fn set_fullscreen(&self, _fullscreen: bool) {}
+
     #[doc(hidden)]
     fn internal(&self, _: crate::InternalToken) -> Option<&dyn WindowAdapterInternal> {
         None

tools/lsp/main.rs

@@ -239,10 +239,6 @@ fn main() {
     if !args.backend.is_empty() {
         std::env::set_var("SLINT_BACKEND", &args.backend);
     }
-    if args.fullscreen {
-        // TODO: Have an API to set the Window fullscreen #3283
-        std::env::set_var("SLINT_FULLSCREEN", "1");
-    }
 
     #[cfg(feature = "preview-engine")]
     {

tools/lsp/preview/native.rs

@@ -150,7 +150,7 @@ pub fn open_ui(sender: &ServerNotifier) {
 }
 
 fn open_ui_impl(preview_state: &mut PreviewState) {
-    let (default_style, show_preview_ui) = {
+    let (default_style, show_preview_ui, fullscreen) = {
         let cache = super::CONTENT_CACHE.get_or_init(Default::default).lock().unwrap();
         let style = cache.config.style.clone();
         let style = if style.is_empty() {
@@ -163,12 +163,14 @@ fn open_ui_impl(preview_state: &mut PreviewState) {
             .hide_ui
             .or_else(|| CLI_ARGS.with(|args| args.get().map(|a| a.no_toolbar.clone())))
             .unwrap_or(false);
-        (style, !hide_ui)
+        let fullscreen = CLI_ARGS.with(|args| args.get().map(|a| a.fullscreen).unwrap_or_default());
+        (style, !hide_ui, fullscreen)
     };
 
     // TODO: Handle Error!
     let ui = preview_state.ui.get_or_insert_with(|| super::ui::create_ui(default_style).unwrap());
     ui.set_show_preview_ui(show_preview_ui);
+    ui.window().set_fullscreen(fullscreen);
     ui.window().on_close_requested(|| {
         let mut cache = super::CONTENT_CACHE.get_or_init(Default::default).lock().unwrap();
         cache.ui_is_visible = false;