chore: Sync with Relm4 new-approach branch

crates/component-system/Cargo.toml

@@ -4,8 +4,14 @@ version = "0.1.0"
 edition = "2021"
 license = "MPL-2.0"
 
-[dependencies]
+[dependencies.tokio]
-async-trait = "0.1.52"
+version = "1.15"
-gtk4 = "0.4.4"
+features = ["rt", "rt-multi-thread", "sync"]
-relm4-macros = "0.4.1"
+
-tokio = { version = "1.15.0", features = ["full"]}
+[dependencies.relm4]
+git = "https://github.com/AaronErhardt/relm4"
+branch = "new-approach"
+
+[dependencies.relm4-macros]
+git = "https://github.com/AaronErhardt/relm4"
+branch = "new-approach"

crates/component-system/README.md

@@ -1,6 +1,6 @@
 # COSMIC Component System
 
-This library is a GTK4 GUI framework inspired by [Relm](https://github.com/antoyo/relm), which is inspired by [Elm](https://guide.elm-lang.org/architecture/). The philosophy for this framework is to isolate custom widgets into reusable components. You start with a custom `Model` type that implements `Component`, which is used to register a component with an optional argument. On registration, the model is used to construct the view and its widgets in the `init_view()` function. An event-handler is also spawned to handle events from both the component and any component emitting events to it. Those events are received and handled in the `update()` function. Both the `init_view()` and `update()` methods also have access to an outbound sender, which the caller can forward and consume however desired. See the examples directory for a demonstration of how to create a component.
+This library is a prototyping area for a rewrite of Relm4's component system.
 
 ## Using a Macro to Define a Component
 
@@ -12,6 +12,10 @@ pub enum MyCustomInputMessage {
     Variant2,
 }
 
+pub enum MyCustomCommand {
+    Action
+}
+
 component! {
     // The model stores the state of this component.
     pub struct MyCustomModel {
@@ -47,17 +51,14 @@ component! {
 
         root.append(&description);
 
-        ComponentInner {
+        Fuselage {
             model: MyCustomModel { state: String::new() },
             widgets: MyCustomWidgets { description },
-            input,
-            output
         }
     }
 
-    // Where events are received, with `component` is the `ComponentInner`,
+    // Updates the model and view. `self` is the model.
-    // and `event` is a `MyCustomInputMessage` which was just received.
+    fn update(&mut self, widgets, event, input, output) {
-    fn update(component, event) {
         match event {
             MyCustomInputMessage::Variant1 => {
 
@@ -67,6 +68,12 @@ component! {
 
             }
         }
+
+        Some(MyCustomCommand::Action)
+    }
+
+    async fn command(command: MyCustomCommand, input) {
+
     }
 }
 ```
@@ -74,7 +81,8 @@ component! {
 Components can be created and have their output events forwarded:
 
 ```rs
-let counter = InfoButton::init("Clicked 0 times".into(), "Click".into())
+let counter = InfoButton::init()
+    .launch("Clicked 0 times".into(), "Click".into())
     .forward(input.clone(), |event| match event {
         InfoButtonOutput::Clicked => AppEvent::Increment
     });
@@ -85,18 +93,5 @@ The handle returned can be used to emit inputs to it, and to get the root widget
 ```rs
 counter.emit(InfoButtonInput::SetDescription(format!("Clicked {} times", count)));
 
-box.append(counter.widget());
+box.append(&counter.widget);
 ```
-
-
-## See Also
-
-[Relm4](https://github.com/AaronErhardt/relm4) uses a similar approach, but closely follows the Elm model. This library was created as an alternative approach that makes developing reusable components with forwardable events simpler.
-
-## License
-
-Licensed under the [Mozilla Public License 2.0](https://choosealicense.com/licenses/mpl-2.0/).
-
-### Contribution
-
-Any contribution intentionally submitted for inclusion in the work by you shall be licensed under the Mozilla Public License 2.0 (MPL-2.0).

crates/component-system/examples/basic/components/app.rs

@@ -21,20 +21,29 @@ component! {
     /// Widgets that are initialized in the view.
     pub struct AppWidgets {
         list: gtk::ListBox,
-        destroyable: Option<Handle<gtk::Box, InfoButtonInput>>,
+        destroyable: Option<Controller<gtk::Box, InfoButtonInput>>,
-        counter: Handle<gtk::Box, InfoButtonInput>,
+        counter: Controller<gtk::Box, InfoButtonInput>,
     }
 
     type Input = AppEvent;
     type Output = ();
-    type Root = gtk::ApplicationWindow {
+    type Root = gtk::Box {
-        Default::default()
+        ccs::view! {
+            root = gtk::Box {
+                set_halign: gtk::Align::Center,
+                set_size_request: args!(400, -1),
+                set_orientation: gtk::Orientation::Vertical,
+            }
+        }
+
+        root
     };
 
-    fn init(app: gtk::Application, root, input, output) {
+    fn init(window: gtk::ApplicationWindow, root, input, _output) {
         let button_group = gtk::SizeGroup::new(gtk::SizeGroupMode::Both);
 
-        let destroyable = InfoButton::init((String::new(), "Destroy".into(), button_group.clone()))
+        let destroyable = InfoButton::init()
+            .launch_stateful((String::new(), "Destroy".into(), button_group.clone()))
             .forward(input.clone(), |event| match event {
                 InfoButtonOutput::Clicked => AppEvent::Destroy,
             });
@@ -45,64 +54,59 @@ component! {
         ));
 
         // Create a counter component, too.
-        let counter = InfoButton::init(("Click me too".into(), "Click".into(), button_group))
+        let counter = InfoButton::init()
+            .launch_stateful(("Click me too".into(), "Click".into(), button_group))
             .forward(input.clone(), |event| match event {
                 InfoButtonOutput::Clicked => AppEvent::Increment,
             });
 
         ccs::view! {
-            container = gtk::Box {
+            list = gtk::ListBox {
-                set_halign: gtk::Align::Center,
-                set_size_request: args!(400, -1),
-                set_orientation: gtk::Orientation::Vertical,
-
-                append: list = &gtk::ListBox {
                 set_selection_mode: gtk::SelectionMode::None,
                 set_hexpand: true,
 
-                    append: destroyable.widget(),
+                append: &destroyable.widget,
-                    append: counter.widget(),
+                append: &counter.widget,
-                }
             }
         }
 
-        root.set_application(Some(&app));
+        root.append(&list);
-        root.set_child(Some(&container));
+        window.set_child(Some(root));
 
-        root.show();
+        Fuselage {
-
-        ComponentInner {
             model: Self::default(),
             widgets: AppWidgets { list, destroyable: Some(destroyable), counter },
-            input,
-            output
         }
     }
 
     /// Updates the view
-    fn update(component, event) {
+    fn update(&mut self, widgets, event, _input, _output) {
-        let &mut ComponentInner { ref mut model, ref mut widgets, .. } = component;
-
         match event {
             AppEvent::Increment => {
-                model.counter += 1;
+                self.counter += 1;
 
                 widgets
                     .counter
                     .emit(InfoButtonInput::SetDescription(format!(
                         "Clicked {} times",
-                        model.counter
+                        self.counter
                     )));
             }
 
             AppEvent::Destroy => {
                 // Components are kept alive by their root GTK widget.
                 if let Some(handle) = widgets.destroyable.take() {
-                    if let Some(parent) = handle.widget().parent() {
+                    if let Some(parent) = handle.widget.parent() {
                         widgets.list.remove(&parent);
                     }
                 }
             }
         }
+
+        None
+    }
+
+    async fn command(_message: (), _input) {
+
     }
 }

crates/component-system/examples/basic/components/info_button.rs

@@ -21,6 +21,7 @@ component! {
     pub struct InfoButtonWidgets {
         description: gtk::Label,
     }
+
     type Input = InfoButtonInput;
     type Output = InfoButtonOutput;
 
@@ -39,7 +40,7 @@ component! {
         root
     };
 
-    fn init(args: (String, String, gtk::SizeGroup), root, input, output) {
+    fn init(args: (String, String, gtk::SizeGroup), root, _input, output) {
         let (desc, button_label, sg) = args;
 
         ccs::view! {
@@ -67,19 +68,23 @@ component! {
 
         sg.add_widget(&button);
 
-        ComponentInner {
+        Fuselage {
             model: InfoButton {},
             widgets: InfoButtonWidgets { description },
-            input,
-            output,
         }
     }
 
-    fn update(component, message) {
+    fn update(&mut self, widgets, message, _input, _output) {
         match message {
             InfoButtonInput::SetDescription(value) => {
-                component.widgets.description.set_text(&value);
+                widgets.description.set_text(&value);
             }
         }
+
+        None
+    }
+
+    async fn command(_message: (), _input) {
+
     }
 }

crates/component-system/examples/basic/main.rs

@@ -6,12 +6,12 @@ extern crate cosmic_component_system as ccs;
 mod components;
 
 use self::components::App;
-use ccs::{AppRunner, Component};
+use ccs::*;
 
 fn main() {
-    gtk4::builders::ApplicationBuilder::new()
+    gtk::builders::ApplicationBuilder::new()
         .application_id("org.pop.CosmicComponentExample")
-        .cosmic_run(|app| {
+        .launch(|_app, window| {
-            App::init(app);
+            App::init().launch_stateful(window);
         });
 }

crates/component-system/src/app_runner.rs

@@ -1,22 +0,0 @@
-// Copyright 2022 System76 <info@system76.com>
-// SPDX-License-Identifier: MPL-2.0
-
-use gtk4::prelude::{ApplicationExt, ApplicationExtManual};
-
-pub trait AppRunner {
-    /// Convenience method to activates and run a GTK4 application.
-    fn cosmic_run<F: Fn(gtk4::Application) + 'static>(self, func: F);
-}
-
-impl AppRunner for gtk4::Application {
-    fn cosmic_run<F: Fn(gtk4::Application) + 'static>(self, func: F) {
-        self.connect_activate(move |app| func(app.clone()));
-        self.run();
-    }
-}
-
-impl AppRunner for gtk4::builders::ApplicationBuilder {
-    fn cosmic_run<F: Fn(gtk4::Application) + 'static>(self, func: F) {
-        self.build().cosmic_run(func);
-    }
-}

crates/component-system/src/component/elmless.rs

@@ -1,90 +0,0 @@
-// Copyright 2022 System76 <info@system76.com>
-// SPDX-License-Identifier: MPL-2.0
-
-use super::*;
-
-/// The basis of a COSMIC widget.
-///
-/// A component takes care of constructing the UI of a widget, managing an event-loop
-/// which handles signals from within the widget, and supports forwarding messages to
-/// the consumer of the component.
-#[async_trait::async_trait]
-pub trait Component: Sized + 'static {
-    /// The arguments that are passed to the init_view method.
-    type InitParams;
-
-    /// The message type that the component accepts as inputs.
-    type Input: 'static;
-
-    /// The message type that the component provides as outputs.
-    type Output: 'static;
-
-    /// The widget that was constructed by the component.
-    type Root: Clone + AsRef<gtk4::Widget>;
-
-    /// The type that's used for storing widgets created for this component.
-    type Widgets: 'static;
-
-    /// Initializes the root widget
-    fn init_root() -> Self::Root;
-
-    fn init_inner(
-        params: Self::InitParams,
-        root_widget: &Self::Root,
-        input: Sender<Self::Input>,
-        output: Sender<Self::Output>,
-    ) -> ComponentInner<Self, Self::Widgets, Self::Input, Self::Output>;
-
-    /// Initializes the component and attaches it to the default local executor.
-    ///
-    /// Spawns an event loop on `glib::MainContext::default()`, which exists
-    /// for as long as the root widget remains alive.
-    fn init(params: Self::InitParams) -> Registered<Self::Root, Self::Input, Self::Output> {
-        let (sender, in_rx) = mpsc::unbounded_channel::<Self::Input>();
-        let (out_tx, output) = mpsc::unbounded_channel::<Self::Output>();
-
-        let root = Self::init_root();
-
-        let mut component = Self::init_inner(params, &root, sender, out_tx);
-
-        let handle = Handle {
-            widget: root,
-            sender: component.input.clone(),
-        };
-
-        let (inner_tx, mut inner_rx) = mpsc::unbounded_channel::<InnerMessage<Self::Input>>();
-
-        handle.widget.as_ref().connect_destroy({
-            let sender = inner_tx.clone();
-            move |_| {
-                let _ = sender.send(InnerMessage::Drop);
-            }
-        });
-
-        spawn_local(async move {
-            while let Some(event) = inner_rx.recv().await {
-                match event {
-                    InnerMessage::Message(event) => {
-                        Self::update(&mut component, event);
-                    }
-
-                    InnerMessage::Drop => break,
-                }
-            }
-        });
-
-        forward(in_rx, inner_tx, InnerMessage::Message);
-
-        Registered {
-            handle,
-            receiver: output,
-        }
-    }
-
-    /// Handles input messages and enables the programmer to update the model and view.
-    #[allow(unused_variables)]
-    fn update(
-        component: &mut ComponentInner<Self, Self::Widgets, Self::Input, Self::Output>,
-        message: Self::Input,
-    );
-}

crates/component-system/src/component/elmlike.rs

@@ -1,112 +0,0 @@
-use super::*;
-
-#[async_trait::async_trait]
-/// Elm-style variant of a Component with view updates separated from input updates
-pub trait ElmComponent: Sized + 'static {
-    /// The arguments that are passed to the init_view method.
-    type InitParams;
-
-    /// The message type that the component accepts as inputs.
-    type Input: 'static + Send;
-
-    /// The message type that the component provides as outputs.
-    type Output: 'static;
-
-    /// Internal commands to perform
-    type Command: 'static + Send;
-
-    /// The widget that was constructed by the component.
-    type Root: Clone + AsRef<gtk4::Widget>;
-
-    /// The type that's used for storing widgets created for this component.
-    type Widgets: 'static;
-
-    /// Initializes the root widget
-    fn init_root() -> Self::Root;
-
-    fn init_inner(
-        params: Self::InitParams,
-        root_widget: &Self::Root,
-        input: Sender<Self::Input>,
-        output: Sender<Self::Output>,
-    ) -> ComponentInner<Self, Self::Widgets, Self::Input, Self::Output>;
-
-    /// Initializes the component and attaches it to the default local executor.
-    ///
-    /// Spawns an event loop on `glib::MainContext::default()`, which exists
-    /// for as long as the root widget remains alive.
-    fn init(params: Self::InitParams) -> Registered<Self::Root, Self::Input, Self::Output> {
-        let (sender, in_rx) = mpsc::unbounded_channel::<Self::Input>();
-        let (out_tx, out_rx) = mpsc::unbounded_channel::<Self::Output>();
-
-        let root = Self::init_root();
-
-        let ComponentInner {
-            mut model,
-            mut widgets,
-            mut input,
-            mut output,
-        } = Self::init_inner(params, &root, sender, out_tx);
-
-        let handle = Handle {
-            widget: root,
-            sender: input.clone(),
-        };
-
-        let (inner_tx, mut inner_rx) = mpsc::unbounded_channel::<InnerMessage<Self::Input>>();
-
-        handle.widget.as_ref().connect_destroy({
-            let sender = inner_tx.clone();
-            move |_| {
-                let _ = sender.send(InnerMessage::Drop);
-            }
-        });
-
-        spawn_local(async move {
-            while let Some(event) = inner_rx.recv().await {
-                match event {
-                    InnerMessage::Message(event) => {
-                        if let Some(command) = model.update(event, &mut input, &mut output) {
-                            let input = input.clone();
-                            tokio::spawn(async move {
-                                if let Some(event) = Self::command(command).await {
-                                    let _ = input.send(event);
-                                }
-                            });
-                        }
-
-                        model.update_view(&mut widgets, &mut input, &mut output);
-                    }
-
-                    InnerMessage::Drop => break,
-                }
-            }
-        });
-
-        forward(in_rx, inner_tx, InnerMessage::Message);
-
-        Registered {
-            handle,
-            receiver: out_rx,
-        }
-    }
-
-    /// Handles input messages and enables the programmer to update the model and view.
-    fn update(
-        &mut self,
-        message: Self::Input,
-        input: &mut Sender<Self::Input>,
-        output: &mut Sender<Self::Output>,
-    ) -> Option<Self::Command>;
-
-    /// Update the UI
-    fn update_view(
-        &mut self,
-        widgets: &mut Self::Widgets,
-        input: &mut Sender<Self::Input>,
-        output: &mut Sender<Self::Output>,
-    );
-
-    /// A command to perform in a background thread.
-    async fn command(message: Self::Command) -> Option<Self::Input>;
-}

crates/component-system/src/component/mod.rs

@@ -1,24 +0,0 @@
-// Copyright 2022 System76 <info@system76.com>
-// SPDX-License-Identifier: MPL-2.0
-
-use crate::*;
-
-mod elmless;
-mod elmlike;
-
-pub use self::elmless::*;
-pub use self::elmlike::*;
-
-/// The pieces that make up the state of the component.
-pub struct ComponentInner<Model, Widgets, Input, Output> {
-    pub model: Model,
-    pub widgets: Widgets,
-    pub input: Sender<Input>,
-    pub output: Sender<Output>,
-}
-
-/// Used to drop the component's event loop when the managed widget is destroyed.
-enum InnerMessage<T> {
-    Drop,
-    Message(T),
-}

crates/component-system/src/handle.rs

@@ -1,68 +0,0 @@
-// Copyright 2022 System76 <info@system76.com>
-// SPDX-License-Identifier: MPL-2.0
-
-use crate::*;
-
-/// Handle to an active widget component in the system.
-pub struct Handle<W, I> {
-    /// The widget that this component manages.
-    pub(crate) widget: W,
-
-    /// Used for emitting events to the component.
-    pub(crate) sender: Sender<I>,
-}
-
-impl<W, I> Widget<W> for Handle<W, I> {
-    fn widget(&self) -> &W {
-        &self.widget
-    }
-}
-
-impl<W, I> Handle<W, I> {
-    pub fn emit(&self, event: I) {
-        let _ = self.sender.send(event);
-    }
-}
-
-/// A newly-registered component which supports destructuring the handle
-/// by forwarding or ignoring outputs from the component.
-pub struct Registered<W: Clone + AsRef<gtk4::Widget>, I, O> {
-    /// Handle to the component that was registered.
-    pub handle: Handle<W, I>,
-
-    /// The outputs being received by the component.
-    pub receiver: Receiver<O>,
-}
-
-impl<W: Clone + AsRef<gtk4::Widget>, I: 'static, O: 'static> Registered<W, I, O> {
-    /// Forwards output events to the designated sender.
-    pub fn forward<X: 'static, F: (Fn(O) -> X) + 'static>(
-        self,
-        sender: Sender<X>,
-        transform: F,
-    ) -> Handle<W, I> {
-        let Registered { handle, receiver } = self;
-        forward(receiver, sender, transform);
-        handle
-    }
-
-    pub fn handle<F: FnMut(O) + 'static>(self, mut func: F) -> Handle<W, I> {
-        let Registered {
-            handle,
-            mut receiver,
-        } = self;
-
-        spawn_local(async move {
-            while let Some(event) = receiver.recv().await {
-                func(event);
-            }
-        });
-
-        handle
-    }
-
-    /// Ignore outputs from the component and take the handle.
-    pub fn ignore(self) -> Handle<W, I> {
-        self.handle
-    }
-}

crates/component-system/src/lib.rs

@@ -1,55 +1,7 @@
 // Copyright 2022 System76 <info@system76.com>
 // SPDX-License-Identifier: MPL-2.0
 
-mod app_runner;
-mod component;
-mod handle;
 mod macros;
 
-use gtk4::prelude::*;
+pub use relm4::*;
-use tokio::sync::mpsc;
-
-pub use self::app_runner::AppRunner;
-pub use self::component::{Component, ComponentInner, ElmComponent};
-pub use self::handle::{Handle, Registered};
-pub use async_trait::async_trait;
-pub use gtk4 as gtk;
 pub use relm4_macros::view;
-
-pub type Sender<T> = mpsc::UnboundedSender<T>;
-pub type Receiver<T> = mpsc::UnboundedReceiver<T>;
-
-/// Provides a convenience function for getting a widget out of a type.
-pub trait Widget<W> {
-    fn widget(&self) -> &W;
-}
-
-pub trait CosmicWidgetExt<W>: Widget<W>
-where
-    W: AsRef<gtk::Widget>,
-{
-    fn attach_size_group(&self, sg: &gtk::SizeGroup) -> &Self {
-        sg.add_widget(self.widget().as_ref());
-        self
-    }
-}
-
-/// Convenience function for forwarding events from a receiver to different sender.
-pub fn forward<I: 'static, O: 'static, F: (Fn(I) -> O) + 'static>(
-    mut receiver: Receiver<I>,
-    sender: Sender<O>,
-    transformer: F,
-) {
-    spawn_local(async move {
-        while let Some(event) = receiver.recv().await {
-            if sender.send(transformer(event)).is_err() {
-                break;
-            }
-        }
-    })
-}
-
-/// Convenience function for spawning tasks on the local executor
-pub fn spawn_local<F: std::future::Future<Output = ()> + 'static>(func: F) {
-    gtk4::glib::MainContext::default().spawn_local(func);
-}

crates/component-system/src/macros.rs

@@ -32,9 +32,15 @@ macro_rules! component {
 
         $(#[$attr5:meta])*
         fn update(
-            $componentv:ident,
+            &mut $modelv:ident,
-            $messagev:ident
+            $widgetsv:ident,
+            $messagev:ident,
+            $inputv2:ident,
+            $outputv2:ident
         ) $update:block
+
+        $(#[$attr6:meta])*
+        async fn command($cmdv:ident: $cmd:ty, $inputv3:ident) { $($cmd_expr:expr)* }
     ) => {
         $(#[$attr])*
         $mvis struct $model {
@@ -46,29 +52,37 @@ macro_rules! component {
             $($wpvis $widgets_property: $widgets_type,)*
         }
 
-        #[cosmic_component_system::async_trait]
+        impl StatefulComponent for $model {
-        impl Component for $model {
+            type Payload = $args;
-            type InitParams = $args;
             type Input = $input;
             type Output = $output;
             type Root = $root;
             type Widgets = $widgets_;
+            type Command = $cmd;
 
             fn init_root() -> Self::Root $init_root
 
             $(#[$attr4])*
-            fn init_inner(
+            fn dock(
-                $argsv: Self::InitParams,
+                $argsv: Self::Payload,
                 $rootv: &Self::Root,
-                $inputv: Sender<Self::Input>,
+                $inputv: &mut Sender<Self::Input>,
-                $outputv: Sender<Self::Output>
+                $outputv: &mut Sender<Self::Output>
-            ) -> ComponentInner<Self, Self::Widgets, Self::Input, Self::Output> $init_view
+            ) -> Fuselage<Self, Self::Widgets> $init_view
 
             $(#[$attr5])*
             fn update(
-                $componentv: &mut ComponentInner<Self, Self::Widgets, Self::Input, Self::Output>,
+                &mut $modelv,
+                $widgetsv: &mut Self::Widgets,
                 $messagev: Self::Input,
-            ) $update
+                $inputv2: &mut Sender<Self::Input>,
+                $outputv2: &mut Sender<Self::Output>
+            ) -> Option<Self::Command> $update
+
+            $(#[$attr6])*
+            fn command($cmdv: $cmd, $inputv3: Sender<Self::Input>) -> CommandFuture {
+                Box::pin(async move { $($cmd_expr)* } )
+            }
         }
     }
 }
@@ -92,7 +106,6 @@ macro_rules! elm_component {
 
         type Input = $input:ty;
         type Output = $output:ty;
-        type Command = $cmd:ty;
         type Root = $root:ty $init_root:block;
 
         $(#[$attr4:meta])*
@@ -105,7 +118,7 @@ macro_rules! elm_component {
 
         $(#[$attr5:meta])*
         fn update(
-            $modelv:ident,
+            &mut $modelv:ident,
             $messagev:ident,
             $inputv2:ident,
             $outputv2:ident
@@ -113,14 +126,14 @@ macro_rules! elm_component {
 
         $(#[$attr6:meta])*
         fn update_view(
-            $modelv2:ident,
+            &$modelv2:ident,
             $widgetsv:ident,
             $inputv3:ident,
             $outputv3:ident
         ) $update_view:block
 
         $(#[$attr7:meta])*
-        async fn command($cmdv:ident) $command_block:block
+        async fn command($cmdv:ident: $cmd:ty, $inputv4:ident) { $($cmd_expr:expr)* }
     ) => {
         $(#[$attr])*
         $mvis struct $model {
@@ -132,43 +145,44 @@ macro_rules! elm_component {
             $($wpvis $widgets_property: $widgets_type,)*
         }
 
-        #[cosmic_component_system::async_trait]
+        impl StatefulComponent for $model {
-        impl ElmComponent for $model {
+            type Payload = $args;
-            type InitParams = $args;
             type Input = $input;
             type Output = $output;
-            type Command = $cmd;
             type Root = $root;
             type Widgets = $widgets_;
+            type Command = $cmd;
 
             fn init_root() -> Self::Root $init_root
 
             $(#[$attr4])*
-            fn init_inner(
+            fn dock(
-                $argsv: Self::InitParams,
+                $argsv: Self::Payload,
                 $rootv: &Self::Root,
-                $inputv: Sender<Self::Input>,
+                $inputv: &mut Sender<Self::Input>,
-                $outputv: Sender<Self::Output>
+                $outputv: &mut Sender<Self::Output>
-            ) -> ComponentInner<Self, Self::Widgets, Self::Input, Self::Output> $init_view
+            ) -> Fuselage<Self, Self::Widgets> $init_view
 
             $(#[$attr5])*
             fn update(
                 &mut $modelv,
                 $messagev: Self::Input,
                 $inputv2: &mut Sender<Self::Input>,
-                $outputv2: &mut Sender<Self::Output>,
+                $outputv2: &mut Sender<Self::Output>
             ) -> Option<Self::Command> $update
 
             $(#[$attr6])*
             fn update_view(
-                &mut $modelv2,
+                &$modelv2,
                 $widgetsv: &mut Self::Widgets,
                 $inputv3: &mut Sender<Self::Input>,
-                $outputv3: &mut Sender<Self::Output>,
+                $outputsv3: &mut Sender<Self::Output>
             ) $update_view
 
             $(#[$attr7])*
-            async fn command($cmdv: Self::Command) -> Option<Self::Input> $command_block
+            fn command($cmdv: $cmd, $inputv4: Sender<Self::Input>) -> CommandFuture {
+                Box::pin(async move { $($cmd_expr)* } )
+            }
         }
     }
 }