Allow implementing a GAction interface

examples/Cargo.toml

@@ -51,3 +51,7 @@ path = "object_subclass/main.rs"
 [[bin]]
 name = "virtual_methods"
 path = "virtual_methods/main.rs"
+
+[[bin]]
+name = "gio_action_impl"
+path = "gio_action_impl/main.rs"

examples/gio_action_impl/action.rs

@@ -0,0 +1,89 @@
+use gio::{prelude::*, subclass::prelude::*};
+
+mod imp {
+    use super::*;
+    use std::cell::OnceCell;
+
+    #[derive(glib::Properties, Default)]
+    #[properties(wrapper_type = super::RenamedAction)]
+    pub struct RenamedAction {
+        #[property(get, construct_only)]
+        pub new_name: OnceCell<glib::GString>,
+
+        #[property(get, construct_only)]
+        pub action: OnceCell<gio::Action>,
+    }
+
+    #[glib::object_subclass]
+    impl ObjectSubclass for RenamedAction {
+        const NAME: &'static str = "ExampleRenamedAction";
+        type Type = super::RenamedAction;
+        type Interfaces = (gio::Action,);
+    }
+
+    #[glib::derived_properties]
+    impl ObjectImpl for RenamedAction {
+        fn properties() -> &'static [glib::ParamSpec] {
+            Self::derived_properties()
+        }
+
+        fn set_property(&self, id: usize, value: &glib::Value, pspec: &glib::ParamSpec) {
+            if !self.delegate_set_property(id, value, pspec) {
+                self.derived_set_property(id, value, pspec);
+            }
+        }
+
+        fn property(&self, id: usize, pspec: &glib::ParamSpec) -> glib::Value {
+            self.delegate_get_property(id, pspec)
+                .unwrap_or_else(|| self.derived_property(id, pspec))
+        }
+    }
+
+    impl ActionImpl for RenamedAction {
+        fn name(&self) -> glib::GString {
+            self.obj().new_name()
+        }
+
+        fn parameter_type(&self) -> Option<glib::VariantType> {
+            self.obj().action().parameter_type()
+        }
+
+        fn state_type(&self) -> Option<glib::VariantType> {
+            self.obj().action().state_type()
+        }
+
+        fn state_hint(&self) -> Option<glib::Variant> {
+            self.obj().action().state_hint()
+        }
+
+        fn is_enabled(&self) -> bool {
+            self.obj().action().is_enabled()
+        }
+
+        fn state(&self) -> Option<glib::Variant> {
+            self.obj().action().state()
+        }
+
+        fn change_state(&self, value: glib::Variant) {
+            self.obj().action().change_state(&value);
+        }
+
+        fn activate(&self, parameter: Option<glib::Variant>) {
+            self.obj().action().activate(parameter.as_ref());
+        }
+    }
+}
+
+glib::wrapper! {
+    pub struct RenamedAction(ObjectSubclass<imp::RenamedAction>)
+        @implements gio::Action;
+}
+
+impl RenamedAction {
+    pub fn new(name: &str, action: &impl IsA<gio::Action>) -> Self {
+        glib::Object::builder()
+            .property("new-name", name)
+            .property("action", action)
+            .build()
+    }
+}

examples/gio_action_impl/main.rs

@@ -0,0 +1,22 @@
+mod action;
+
+use gio::prelude::*;
+
+fn main() {
+    let action = gio::SimpleAction::new("bark", Some(glib::VariantTy::STRING));
+    action.connect_activate(|_, p| {
+        let target = p.unwrap().str().unwrap();
+        println!("Woof, {}!", target);
+    });
+
+    let renamed_action = action::RenamedAction::new("meow", &action);
+
+    let group = gio::SimpleActionGroup::new();
+    group.add_action(&action);
+    group.add_action(&renamed_action);
+
+    println!("actions = {:?}", group.list_actions());
+
+    group.activate_action("bark", Some(&"postman".to_variant()));
+    group.activate_action("meow", Some(&"milkman".to_variant()));
+}