widget state

src/default/mod.rs

@@ -17,6 +17,7 @@ mod event;
 mod input;
 mod render;
 mod sense;
+mod state;
 mod task;
 
 pub use app::*;
@@ -25,6 +26,7 @@ pub use event::*;
 pub use input::*;
 pub use render::*;
 pub use sense::*;
+pub use state::*;
 pub use task::*;
 
 pub type Proxy<Event> = EventLoopProxy<Event>;
@@ -98,6 +100,7 @@ pub struct DefaultRsc<State: 'static> {
     pub ui: UiData,
     pub events: EventManager<Self>,
     pub tasks: Tasks<Self>,
+    pub state: WidgetState,
     _state: PhantomData<State>,
 }
 
@@ -109,11 +112,16 @@ impl<State> DefaultRsc<State> {
                 ui: Default::default(),
                 events: Default::default(),
                 tasks,
+                state: Default::default(),
                 _state: Default::default(),
             },
             recv,
         )
     }
+
+    pub fn create_state<T: 'static>(&mut self, id: impl IdLike, data: T) -> WeakState<T> {
+        self.state.add(id.id(), data)
+    }
 }
 
 impl<State> UiRsc for DefaultRsc<State> {
@@ -158,6 +166,16 @@ impl<State: 'static> HasTasks for DefaultRsc<State> {
     }
 }
 
+impl<State: 'static> HasWidgetState for DefaultRsc<State> {
+    fn widget_state(&self) -> &WidgetState {
+        &self.state
+    }
+
+    fn widget_state_mut(&mut self) -> &mut WidgetState {
+        &mut self.state
+    }
+}
+
 pub struct DefaultApp<State: DefaultAppState> {
     rsc: DefaultRsc<State>,
     render: UiRenderState,
@@ -289,3 +307,47 @@ impl<State: DefaultAppState> AppState for DefaultApp<State> {
         self.state.exit(&mut self.rsc, &mut self.render);
     }
 }
+
+pub trait RscIdx<Rsc> {
+    type Output;
+    fn get(self, rsc: &Rsc) -> &Self::Output;
+    fn get_mut(self, rsc: &mut Rsc) -> &mut Self::Output;
+}
+
+impl<State: 'static, I: RscIdx<DefaultRsc<State>>> std::ops::Index<I> for DefaultRsc<State> {
+    type Output = I::Output;
+
+    fn index(&self, index: I) -> &Self::Output {
+        index.get(self)
+    }
+}
+
+impl<State: 'static, I: RscIdx<DefaultRsc<State>>> std::ops::IndexMut<I> for DefaultRsc<State> {
+    fn index_mut(&mut self, index: I) -> &mut Self::Output {
+        index.get_mut(self)
+    }
+}
+
+impl<W: Widget, Rsc: UiRsc> RscIdx<Rsc> for WeakWidget<W> {
+    type Output = W;
+
+    fn get(self, rsc: &Rsc) -> &Self::Output {
+        &rsc.ui().widgets[self]
+    }
+
+    fn get_mut(self, rsc: &mut Rsc) -> &mut Self::Output {
+        &mut rsc.ui_mut().widgets[self]
+    }
+}
+
+impl<T: 'static, Rsc: HasWidgetState> RscIdx<Rsc> for WeakState<T> {
+    type Output = T;
+
+    fn get(self, rsc: &Rsc) -> &Self::Output {
+        rsc.widget_state().get(self)
+    }
+
+    fn get_mut(self, rsc: &mut Rsc) -> &mut Self::Output {
+        rsc.widget_state_mut().get_mut(self)
+    }
+}

src/default/state.rs

@@ -0,0 +1,67 @@
+use iris_core::{WidgetId, util::HashMap};
+use std::{
+    any::{Any, TypeId},
+    marker::PhantomData,
+};
+
+#[derive(Clone, Copy, PartialEq, Eq, Hash)]
+struct Key {
+    id: WidgetId,
+    ty: TypeId,
+    i: usize,
+}
+
+#[derive(Default)]
+pub struct WidgetState {
+    counts: HashMap<(WidgetId, TypeId), usize>,
+    map: HashMap<Key, Box<dyn Any>>,
+}
+
+impl WidgetState {
+    pub fn new() -> Self {
+        Self::default()
+    }
+    pub fn add<T: 'static>(&mut self, id: WidgetId, data: T) -> WeakState<T> {
+        let ty = TypeId::of::<T>();
+        let count = self.counts.entry((id, ty)).or_default();
+        let key = Key { ty, i: *count, id };
+        self.map.insert(key, Box::new(data));
+        *count += 1;
+        WeakState {
+            key,
+            _pd: PhantomData,
+        }
+    }
+    pub fn remove<T>(&mut self, state: WeakState<T>) {
+        self.map.remove(&state.key);
+    }
+    pub fn get<T: 'static>(&self, state: WeakState<T>) -> &T {
+        self.map.get(&state.key).unwrap().downcast_ref().unwrap()
+    }
+    pub fn get_mut<T: 'static>(&mut self, state: WeakState<T>) -> &mut T {
+        self.map
+            .get_mut(&state.key)
+            .unwrap()
+            .downcast_mut()
+            .unwrap()
+    }
+}
+
+#[derive(Clone, Copy)]
+pub struct WeakState<T> {
+    key: Key,
+    _pd: PhantomData<T>,
+}
+
+pub trait HasWidgetState {
+    fn widget_state(&self) -> &WidgetState;
+    fn widget_state_mut(&mut self) -> &mut WidgetState;
+}
+
+impl<'a, T: 'static> FnOnce<(&'a mut WidgetState,)> for WeakState<T> {
+    type Output = &'a mut T;
+
+    extern "rust-call" fn call_once(self, (state,): (&'a mut WidgetState,)) -> Self::Output {
+        state.get_mut(self)
+    }
+}