add example

Cargo.toml

@@ -93,6 +93,7 @@ members = [
     "examples/pure/pick_list",
     "examples/pure/todos",
     "examples/pure/tour",
+    "examples/pure/stateless_component",
     "examples/websocket",
 ]
 

examples/pure/stateless_component/Cargo.toml

@@ -0,0 +1,12 @@
+[package]
+name = "stateless_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/stateless_component/src/main.rs

@@ -0,0 +1,101 @@
+use iced::pure::{button, text};
+use iced::pure::{Element, Sandbox};
+use iced::Settings;
+
+use custom_text::custom_text;
+
+pub fn main() -> iced::Result {
+    Mode::run(Settings::default())
+}
+
+enum Mode {
+    Standard,
+    Custom,
+}
+
+#[derive(Debug, Clone, Copy)]
+enum Message {
+    SwitchToComponent,
+}
+
+impl Sandbox for Mode {
+    type Message = Message;
+
+    fn new() -> Self {
+        Self::Standard
+    }
+
+    fn title(&self) -> String {
+        String::from("Stateless Component Bug")
+    }
+
+    fn update(&mut self, message: Message) {
+        match message {
+            Message::SwitchToComponent => *self = Mode::Custom,
+        }
+    }
+
+    fn view(&self) -> Element<Message> {
+        match self {
+            Self::Standard => button(text("Click to Panic"))
+                .on_press(Message::SwitchToComponent)
+                .into(),
+            Self::Custom => button(custom_text("..")).into(),
+        }
+    }
+}
+
+mod custom_text {
+    use iced::pure::text;
+    use iced_lazy::pure::{self, Component};
+    use iced_native::text;
+    use iced_pure::Element;
+
+    pub struct CustomText<'a> {
+        text: &'a str,
+    }
+
+    pub fn custom_text<'a>(text: &'a str) -> CustomText<'a> {
+        CustomText { text }
+    }
+
+    #[derive(Debug, Clone)]
+    pub enum Event {}
+
+    impl<'a> CustomText<'a> {
+        pub fn new(text: &'a str) -> Self {
+            Self { text }
+        }
+    }
+
+    impl<'a, Message, Renderer> Component<Message, Renderer> for CustomText<'a>
+    where
+        Renderer: text::Renderer + 'static,
+    {
+        type State = ();
+        type Event = Event;
+
+        fn update(
+            &mut self,
+            _state: &mut Self::State,
+            _event: Event,
+        ) -> Option<Message> {
+            None
+        }
+
+        fn view(&self, _state: &Self::State) -> Element<Event, Renderer> {
+            text(self.text).into()
+        }
+    }
+
+    impl<'a, Message, Renderer> From<CustomText<'a>>
+        for Element<'a, Message, Renderer>
+    where
+        Message: 'a,
+        Renderer: 'static + text::Renderer,
+    {
+        fn from(x: CustomText<'a>) -> Self {
+            pure::component(x)
+        }
+    }
+}