subclass the WelcomePageWidget

src/widgets/pages/welcome.rs

@@ -10,6 +10,7 @@ use gtk::glib::clone;
 #[cfg(feature = "video")]
 use gtk::glib::{Receiver, Sender};
 use gtk::prelude::*;
+use gtk::subclass::prelude::*;
 #[cfg(feature = "video")]
 use std::cell::RefCell;
 
@@ -20,26 +21,28 @@ pub enum Action {
     VideoUp,
 }
 
-pub struct WelcomePageWidget {
-    pub widget: gtk::Box,
+mod imp {
+    use super::*;
+
+    #[derive(Debug)]
+    pub struct WelcomePageWidget {
         #[cfg(feature = "video")]
         player: gst_player::Player,
         #[cfg(feature = "video")]
         receiver: RefCell<Option<Receiver<Action>>>,
         #[cfg(feature = "video")]
         sender: Sender<Action>,
-}
-
-impl WelcomePageWidget {
-    pub fn new() -> Self {
-        let widget = gtk::Box::new(gtk::Orientation::Horizontal, 0);
+    }
 
+    impl Default for WelcomePageWidget {
+        fn default() -> Self {
             #[cfg(feature = "video")]
             let player = {
                 let dispatcher = gst_player::PlayerGMainContextSignalDispatcher::new(None);
                 let sink = gst::ElementFactory::make("gtksink", None)
                 .expect("Missing dependency: element gtksink is needed (usually, in gstreamer-plugins-good or in gst-plugin-gtk).");
-            let renderer = gst_player::PlayerVideoOverlayVideoRenderer::with_sink(&sink).upcast();
+                let renderer =
+                    gst_player::PlayerVideoOverlayVideoRenderer::with_sink(&sink).upcast();
                 gst_player::Player::new(
                     Some(&renderer),
                     Some(&dispatcher.upcast::<gst_player::PlayerSignalDispatcher>()),
@@ -50,21 +53,32 @@ impl WelcomePageWidget {
             #[cfg(feature = "video")]
             let receiver = RefCell::new(Some(r));
 
-        let welcome_page = Self {
-            widget,
+            Self {
                 #[cfg(feature = "video")]
                 player,
                 #[cfg(feature = "video")]
                 sender,
                 #[cfg(feature = "video")]
                 receiver,
-        };
+            }
+        }
+    }
 
-        welcome_page.init();
-        welcome_page
+    #[glib::object_subclass]
+    impl ObjectSubclass for WelcomePageWidget {
+        const NAME: &'static str = "WelcomePageWidget";
+        type ParentType = gtk::Box;
+        type Type = super::WelcomePageWidget;
     }
 
-    fn init(&self) {
+    impl ObjectImpl for WelcomePageWidget {
+        fn constructed(&self, widget: &Self::Type) {
+            let layout_manager = widget
+                .layout_manager()
+                .map(|l| l.downcast::<gtk::BoxLayout>().unwrap())
+                .unwrap();
+            layout_manager.set_orientation(gtk::Orientation::Vertical);
+
             let container = gtk::Box::builder()
                 .orientation(gtk::Orientation::Vertical)
                 .spacing(0)
@@ -75,8 +89,8 @@ impl WelcomePageWidget {
                 .margin_top(24)
                 .margin_bottom(24)
                 .build();
-        self.widget.add_css_class("page");
-        self.widget.add_css_class("welcome-page");
+            widget.add_css_class("page");
+            widget.add_css_class("welcome-page");
 
             let clamp = adw::Clamp::new();
             clamp.set_child(Some(&container));
@@ -96,21 +110,12 @@ impl WelcomePageWidget {
             let header = {
                 let video_widget = self
                     .player
-                .get_pipeline()
-                .get_property("video-sink")
-                .unwrap()
-                .get::<gst::Element>()
-                .expect("The player of a VideoPlayerWidget should not use the default sink.")
-                .unwrap()
-                .get_property("widget")
-                .unwrap()
-                .get::<gtk::Widget>()
-                .unwrap()
-                .unwrap();
+                    .pipeline()
+                    .property::<gst::Element>("video-sink")
+                    .property::<gtk::Widget>("widget");
 
                 video_widget.set_size_request(-1, 360);
                 video_widget.set_property("ignore-alpha", &false).unwrap();
-            video_widget.show();
                 video_widget.add_css_class("video");
                 video_widget
             };
@@ -172,6 +177,21 @@ impl WelcomePageWidget {
             text.set_margin_top(12);
             container.append(&text);
 
-        self.widget.append(&clamp);
+            widget.append(&clamp);
+            self.parent_constructed(widget);
+        }
+    }
+    impl WidgetImpl for WelcomePageWidget {}
+    impl BoxImpl for WelcomePageWidget {}
+}
+
+glib::wrapper! {
+    pub struct WelcomePageWidget(ObjectSubclass<imp::WelcomePageWidget>)
+        @extends gtk::Widget, gtk::Box;
+}
+
+impl WelcomePageWidget {
+    pub fn new() -> Self {
+        glib::Object::new(&[]).unwrap()
     }
 }

src/widgets/window.rs

@@ -34,7 +34,7 @@ mod imp {
                 widget.add_css_class("devel");
             }
 
-            self.paginator.add_page(WelcomePageWidget::new().widget);
+            self.paginator.add_page(WelcomePageWidget::new());
             self.paginator.add_page(ImagePageWidget::new(
                 "/org/gnome/Tour/overview.svg",
                 gettext("Get an Overview"),