Example

wayland-server/examples/delegated.rs

@@ -0,0 +1,84 @@
+use delegated::{OutputHandler, OutputManagerState};
+use wayland_server::Display;
+
+mod delegated {
+    use wayland_server::{
+        backend::GlobalId,
+        protocol::wl_output::{self, WlOutput},
+        Client, DataInit, Dispatch, DisplayHandle, GlobalDispatch, New,
+    };
+
+    pub trait OutputHandler {
+        fn state(&mut self) -> &mut OutputManagerState;
+        fn some_callback(&mut self);
+    }
+
+    pub struct OutputManagerState {
+        global_id: GlobalId,
+    }
+
+    impl OutputManagerState {
+        pub fn create_delegated_global<D>(dh: &DisplayHandle) -> Self
+        where
+            D: OutputHandler + 'static,
+        {
+            let global_id = dh.create_delegated_global::<D, WlOutput, (), Self>(4, ());
+            Self { global_id }
+        }
+
+        pub fn gloabl_id(&self) -> GlobalId {
+            self.global_id.clone()
+        }
+    }
+
+    impl<D: OutputHandler> GlobalDispatch<WlOutput, (), D> for OutputManagerState {
+        fn bind(
+            state: &mut D,
+            _handle: &DisplayHandle,
+            _client: &Client,
+            resource: New<WlOutput>,
+            _global_data: &(),
+            data_init: &mut DataInit<'_, D>,
+        ) {
+            let _output = data_init.init_delegated::<_, _, Self>(resource, ());
+
+            state.state();
+            state.some_callback();
+        }
+    }
+
+    impl<D> Dispatch<WlOutput, (), D> for OutputManagerState {
+        fn request(
+            _state: &mut D,
+            _client: &Client,
+            _resource: &WlOutput,
+            _request: wl_output::Request,
+            _data: &(),
+            _dhandle: &DisplayHandle,
+            _data_init: &mut DataInit<'_, D>,
+        ) {
+        }
+    }
+}
+
+struct App {
+    output_state: OutputManagerState,
+}
+
+impl OutputHandler for App {
+    fn state(&mut self) -> &mut OutputManagerState {
+        &mut self.output_state
+    }
+
+    fn some_callback(&mut self) {}
+}
+
+fn main() {
+    let display = Display::<App>::new().unwrap();
+
+    let output_state = OutputManagerState::create_delegated_global::<App>(&display.handle());
+
+    let app = App { output_state };
+
+    display.handle().remove_global::<App>(app.output_state.gloabl_id());
+}