add example

Cargo.toml

@@ -89,6 +89,7 @@ members = [
     "examples/pure/component",
     "examples/pure/counter",
     "examples/pure/game_of_life",
+    "examples/pure/nested_component",
     "examples/pure/pane_grid",
     "examples/pure/pick_list",
     "examples/pure/todos",

examples/pure/nested_component/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "pure_nested_component"
+version = "0.1.0"
+authors = ["Héctor Ramón Jiménez <hector0193@gmail.com>"]
+edition = "2021"
+publish = false
+
+[dependencies]
+iced = { path = "../../..", features = ["debug", "pure"] }
+iced_native = { path = "../../../native" }
+iced_lazy = { path = "../../../lazy", features = ["pure"] }
+iced_pure = { path = "../../../pure" }

examples/pure/nested_component/src/main.rs

@@ -0,0 +1,166 @@
+use iced::pure::container;
+use iced::pure::{Element, Sandbox};
+use iced::{Length, Settings};
+
+use counter::counter;
+
+pub fn main() -> iced::Result {
+    Component::run(Settings::default())
+}
+
+#[derive(Default)]
+struct Component;
+
+#[derive(Debug, Clone, Copy)]
+enum Message {}
+
+impl Sandbox for Component {
+    type Message = Message;
+
+    fn new() -> Self {
+        Self::default()
+    }
+
+    fn title(&self) -> String {
+        String::from("Component - Iced")
+    }
+
+    fn update(&mut self, _message: Message) {}
+
+    fn view(&self) -> Element<Message> {
+        container(counter())
+            .padding(20)
+            .height(Length::Fill)
+            .center_y()
+            .into()
+    }
+}
+
+mod counter {
+    use iced::pure::{column, text};
+    use iced_lazy::pure::{self, Component};
+    use iced_native::text;
+    use iced_pure::Element;
+
+    use custom_button::custom_button;
+
+    pub struct Counter;
+
+    pub fn counter() -> Counter {
+        Counter::new()
+    }
+
+    #[derive(Debug, Clone)]
+    pub enum Event {
+        IncrementPressed,
+    }
+
+    impl Counter {
+        pub fn new() -> Self {
+            Self {}
+        }
+    }
+
+    #[derive(Default)]
+    pub struct State {
+        count: u32,
+    }
+
+    impl<Message, Renderer> Component<Message, Renderer> for Counter
+    where
+        Renderer: text::Renderer + 'static,
+    {
+        type State = State;
+        type Event = Event;
+
+        fn update(
+            &mut self,
+            state: &mut Self::State,
+            event: Event,
+        ) -> Option<Message> {
+            match event {
+                Event::IncrementPressed => {
+                    state.count += 1;
+
+                    None
+                }
+            }
+        }
+
+        fn view(&self, state: &Self::State) -> Element<Event, Renderer> {
+            column()
+                .push(text(&state.count.to_string()))
+                .push(custom_button("Increment", Event::IncrementPressed))
+                .into()
+        }
+    }
+
+    impl<'a, Message, Renderer> From<Counter> for Element<'a, Message, Renderer>
+    where
+        Message: 'a,
+        Renderer: 'static + text::Renderer,
+    {
+        fn from(counter: Counter) -> Self {
+            pure::component(counter)
+        }
+    }
+
+    mod custom_button {
+        use iced::pure::{button, text};
+        use iced_lazy::pure::{self, Component};
+        use iced_native::text;
+        use iced_pure::Element;
+
+        pub struct CustomButton<'a, Message> {
+            text: &'a str,
+            on_press: Message,
+        }
+
+        pub fn custom_button<'a, Message>(
+            text: &'a str,
+            on_press: Message,
+        ) -> CustomButton<'a, Message> {
+            CustomButton { text, on_press }
+        }
+
+        #[derive(Clone)]
+        pub enum Event {
+            Press,
+        }
+
+        impl<'a, Message, Renderer> Component<Message, Renderer>
+            for CustomButton<'a, Message>
+        where
+            Message: Clone,
+            Renderer: iced_native::Renderer + text::Renderer + 'static,
+        {
+            type State = ();
+            type Event = Event;
+
+            fn update(
+                &mut self,
+                _state: &mut Self::State,
+                event: Event,
+            ) -> Option<Message> {
+                match event {
+                    Event::Press => Some(self.on_press.clone()),
+                }
+            }
+
+            fn view(&self, _state: &Self::State) -> Element<Event, Renderer> {
+                button(text(self.text)).on_press(Event::Press).into()
+            }
+        }
+
+        impl<'a, Message, Renderer> From<CustomButton<'a, Message>>
+            for Element<'a, Message, Renderer>
+        where
+            Message: Clone + 'a,
+            Renderer: 'static + text::Renderer,
+        {
+            fn from(custom_button: CustomButton<'a, Message>) -> Self {
+                pure::component(custom_button)
+            }
+        }
+    }
+}