Clean up shared UI runtime state

src/android/view.rs

@@ -11,13 +11,7 @@ use android_view::{
     },
     ndk::event::{Axis, Keycode, MotionAction},
 };
-use std::{
-    cell::RefCell,
-    marker::{PhantomData, Sized},
-    rc::Rc,
-    sync::Arc,
-    time::Instant,
-};
+use std::{cell::RefCell, marker::Sized, rc::Rc, sync::Arc, time::Instant};
 
 use super::{
     access::{AndroidAccessSource, NullActionHandler, raise_if_enabled},
@@ -25,10 +19,7 @@ use super::{
     render::{AndroidRedrawHandle, AndroidRenderer},
 };
 
-/// The android-view analogue of `default::DefaultUiState`. `renderer` is an
-/// `Option` because a `SurfaceView`'s surface does not outlive backgrounding
-/// the way a winit `Window` does -- `surfaceDestroyed`/`surfaceCreated` can
-/// happen any number of times over the life of one `IrisViewPeer`.
+/// Android host state. The renderer follows the `SurfaceView` lifecycle.
 /// How many frames after each `surface_changed` `render()` logs a full
 /// diagnostic line for -- see the log site's own comment.
 const DIAGNOSTIC_FRAMES: u64 = 10;
@@ -39,24 +30,13 @@ pub struct AndroidUiState {
     pub focus: Option<WeakWidget<TextEdit>>,
     pub cursor: CursorState,
     pub last_click: Instant,
-    /// The IME preedit's previous length, in `char`s -- the same
-    /// re-send-the-whole-composition bookkeeping `default::DefaultUiState`
-    /// keeps for winit's `Ime::Preedit`, since android-view's
-    /// `setComposingText` has the identical shape (see `android/ime.rs`).
+    /// Previous IME preedit length, in characters.
     pub compose_len: usize,
-    /// Set by `attr::FocusHost::focus_gained` when a `TextEdit` is focused;
-    /// consumed by the touch handler after the sensor pass finishes, since
-    /// showing the keyboard is a JNI call and `focus_gained` runs deep
-    /// inside the platform-agnostic sensor dispatch with no `CallbackCtx`
-    /// in reach.
+    /// Deferred until the input callback regains access to JNI.
     pub pending_show_keyboard: bool,
-    /// A URL a tapped link asked the platform to open, for the same
-    /// reason `pending_show_keyboard` is a flag rather than a call --
-    /// see `android/platform.rs`.
+    /// Also deferred until a JNI callback is available.
     pub pending_open_url: Option<String>,
-    /// Window insets, filled in from outside the normal `ViewPeer` callback
-    /// path -- see `android/insets.rs` for why they need a registry of
-    /// their own.
+    /// Filled by the native insets callback registered in `android/insets.rs`.
     shared: Rc<RefCell<Shared>>,
     pub access_adapter: AccessAdapter,
     pub access: AccessTree,
@@ -132,13 +112,7 @@ pub trait AndroidAppState: HasAndroidUiState {
     fn on_insets_changed(&mut self, rsc: &mut AndroidRsc<Self>, insets: WindowInsets) {}
 }
 
-/// `insets::Insets` as `f32`, for the widget-facing callback above -- a
-/// distinct type from `insets::Insets` so a caller of `on_insets_changed`
-/// is not coupled to that module's own (`i32`, JNI-shaped) representation.
-/// Both are physical pixels; this used to divide by `content_scale` into a
-/// separate *logical* unit (hence the old name, `LogicalInsets`), back when
-/// the rest of layout was logical too -- see `AndroidUiState::content_scale`'s
-/// field comment for why that stopgap is gone.
+/// Widget-facing insets in physical pixels, decoupled from JNI's integer shape.
 #[derive(Clone, Copy, Default, Debug, PartialEq)]
 pub struct WindowInsets {
     pub left: f32,
@@ -166,66 +140,7 @@ impl WindowInsets {
     }
 }
 
-pub struct AndroidRsc<State: 'static> {
-    pub ui: Ui,
-    pub events: EventManager<Self>,
-    pub tasks: Tasks<Self>,
-    pub state: WidgetState,
-    _state: PhantomData<State>,
-}
-
-impl<State> AndroidRsc<State> {
-    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 AndroidRsc<State> {
-    fn ui(&self) -> &Ui {
-        &self.ui
-    }
-    fn ui_mut(&mut self) -> &mut Ui {
-        &mut self.ui
-    }
-    fn on_draw(&mut self, active: &ActiveData) {
-        self.events.draw(active);
-    }
-    fn on_undraw(&mut self, active: &ActiveData) {
-        self.events.undraw(active);
-    }
-    fn on_remove(&mut self, id: WidgetId) {
-        self.events.remove(id);
-        self.state.remove(id);
-    }
-}
-
-impl<State: 'static> HasState for AndroidRsc<State> {
-    type State = State;
-}
-
-impl<State: 'static> HasEvents for AndroidRsc<State> {
-    fn events(&self) -> &EventManager<Self> {
-        &self.events
-    }
-    fn events_mut(&mut self) -> &mut EventManager<Self> {
-        &mut self.events
-    }
-}
-
-impl<State: 'static> HasTasks for AndroidRsc<State> {
-    fn tasks_mut(&mut self) -> &mut Tasks<Self> {
-        &mut self.tasks
-    }
-}
-
-impl<State: 'static> HasWidgetState for AndroidRsc<State> {
-    fn widget_state(&self) -> &WidgetState {
-        &self.state
-    }
-    fn widget_state_mut(&mut self) -> &mut WidgetState {
-        &mut self.state
-    }
-}
+pub type AndroidRsc<State> = AppRsc<State>;
 
 /// The `ViewPeer` android-view dispatches every callback to. One per
 /// `RustView` instance; `new_peer` (below) builds it and hands the id to
@@ -234,30 +149,10 @@ pub struct IrisViewPeer<State: AndroidAppState> {
     pub(super) rsc: AndroidRsc<State>,
     pub(super) state: State,
     task_recv: TaskMsgReceiver<AndroidRsc<State>>,
-    /// The one ruler this view dates everything on: touch samples in
-    /// `on_touch_event` and the `Choreographer` frame time in `do_frame`.
-    /// Anchored by whichever of the two arrives first and never
-    /// re-anchored after, which is what lets a fling be advanced on the
-    /// same clock the gesture that launched it was measured on. Its path
-    /// out is the peer's own drop: it holds nothing but three numbers and
-    /// is meaningless to any other view.
+    /// Converts input and Choreographer timestamps onto one monotonic clock.
     device_clock: Option<DeviceClock>,
 }
 
-impl<State: 'static, I: RscIdx<AndroidRsc<State>>> std::ops::Index<I> for AndroidRsc<State> {
-    type Output = I::Output;
-
-    fn index(&self, index: I) -> &Self::Output {
-        index.get(self)
-    }
-}
-
-impl<State: 'static, I: RscIdx<AndroidRsc<State>>> std::ops::IndexMut<I> for AndroidRsc<State> {
-    fn index_mut(&mut self, index: I) -> &mut Self::Output {
-        index.get_mut(self)
-    }
-}
-
 impl<State: AndroidAppState> IrisViewPeer<State> {
     fn drain_tasks(&mut self) {
         while let Ok(update) = self.task_recv.try_recv() {
@@ -298,7 +193,7 @@ impl<State: AndroidAppState> IrisViewPeer<State> {
     /// Common tail for every callback that might have changed the cursor,
     /// the text focus, or the widget tree: run the sensors that touch
     /// input feeds, then ask for a frame if the result needs drawing.
-    /// Mirrors `default::DefaultApp::window_event`'s tail, split across
+    /// Mirrors `desktop::DesktopApp::window_event`'s tail, split across
     /// android-view's several entry points instead of winit's one.
     pub(super) fn after_input(&mut self, ctx: &mut CallbackCtx) {
         self.run_input_frame(ctx);
@@ -322,6 +217,42 @@ impl<State: AndroidAppState> IrisViewPeer<State> {
             .get_or_insert_with(|| DeviceClock::anchored(Instant::now(), event_time, oldest))
     }
 
+    fn generic_motion(&mut self, ctx: &mut CallbackCtx, event: &MotionEvent<'_>) -> bool {
+        let action = event.action_masked(&mut ctx.env);
+        let event_time = event.event_time_nanos(&mut ctx.env);
+        let mut clock = self.device_clock(event_time, event_time);
+        let at = clock.sample(event_time);
+        self.device_clock = Some(clock);
+
+        let ui = self.state.android_state_mut();
+        ui.cursor.time = at;
+        ui.cursor.pos = vec2(event.x(&mut ctx.env), event.y(&mut ctx.env));
+        ui.cursor.exists = !matches!(action, MotionAction::HoverExit);
+
+        let buttons = event.button_state(&mut ctx.env);
+        ui.cursor.buttons.left.update(buttons.primary());
+        ui.cursor.buttons.right.update(buttons.secondary());
+        ui.cursor.buttons.middle.update(buttons.teriary());
+
+        match action {
+            MotionAction::HoverEnter
+            | MotionAction::HoverMove
+            | MotionAction::HoverExit
+            | MotionAction::ButtonPress
+            | MotionAction::ButtonRelease => {}
+            MotionAction::Scroll => {
+                ui.cursor.scroll_delta = vec2(
+                    event.axis(&mut ctx.env, Axis::Hscroll, 0),
+                    event.axis(&mut ctx.env, Axis::Vscroll, 0),
+                );
+            }
+            _ => return false,
+        }
+
+        self.after_input(ctx);
+        true
+    }
+
     fn window_size(&self) -> Vec2 {
         let ui_state = self.state.android_state();
         match &ui_state.renderer {
@@ -514,27 +445,14 @@ impl<State: AndroidAppState> ViewPeer for IrisViewPeer<State> {
     ) -> bool {
         self.drain_tasks();
         let action = event.action_masked(&mut ctx.env);
-        // Device (physical) pixels, same space layout now uses throughout
-        // -- see `AndroidUiState::content_scale`'s field comment.
+        // MotionEvent and layout both use physical pixels.
         let x = event.x(&mut ctx.env);
         let y = event.y(&mut ctx.env);
-        // The event's own clock, converted through the view's one anchor
-        // -- taken on whichever of a touch or a frame callback came first.
-        // Android reports sample times in the `SystemClock.uptimeMillis()`
-        // base, which is the same `CLOCK_MONOTONIC` an `Instant` reads, so
-        // a single `(Instant, nanos)` pair converts every later sample
-        // exactly. Anchoring **once** rather than per event is what keeps
-        // the times ordered, and anchoring on the first event's *oldest*
-        // sample rather than on its own time is what keeps that event's
-        // batch from collapsing onto one instant -- `sense::DeviceClock`'s
-        // doc has both, and owns the arithmetic so it can be unit-tested
-        // off a device (`sense_tests.rs`). See `CursorState::time`.
+        // Use the event clock so batched movement keeps its real timing.
         let event_time = event.event_time_nanos(&mut ctx.env);
         let history = event.history_size(&mut ctx.env);
         let mut clock = match self.device_clock {
             Some(clock) => clock,
-            // Only the call that anchors needs the batch's oldest sample,
-            // so the JNI read for it stays off the per-event path.
             None => {
                 let oldest = if history > 0 {
                     event.historical_event_time_nanos(&mut ctx.env, 0)
@@ -544,24 +462,12 @@ impl<State: AndroidAppState> ViewPeer for IrisViewPeer<State> {
                 self.device_clock(event_time, oldest)
             }
         };
-        // `iris::input`'s own doc (`sense::log_input_event`): collected
-        // only when tracing is on, since this is otherwise a `Vec` per
-        // `MotionEvent` for a line nobody is reading -- the JNI reads
-        // themselves (`historical_axis`/`historical_event_time_nanos`
-        // below) already happen unconditionally, for the replay this
-        // function does regardless of tracing.
+        // Avoid allocating trace history when input tracing is disabled.
         let trace_input = crate::diagnostics::trace_enabled();
         let mut historical_ms: Vec<(u64, f32, f32)> = Vec::new();
 
         if matches!(action, MotionAction::Move) {
-            // Android documents the historical samples as oldest first and
-            // the event's own sample as the newest of the batch; everything
-            // downstream (`VelocityTracker`, `DragArbiter`'s long-press
-            // clock) assumes it, so say so here rather than at each reader.
-            // `DeviceClock::sample` is what asserts it, and it carries the
-            // last sample seen *across* events, so the first sample of
-            // every event is checked against the previous event's last one
-            // rather than against the anchor.
+            // Android orders history oldest-first; `sample` checks monotonicity.
             for pos in 0..history {
                 let hx = event.historical_axis(&mut ctx.env, Axis::X, 0, pos);
                 let hy = event.historical_axis(&mut ctx.env, Axis::Y, 0, pos);
@@ -616,6 +522,38 @@ impl<State: AndroidAppState> ViewPeer for IrisViewPeer<State> {
         true
     }
 
+    fn on_generic_motion_event<'local>(
+        &mut self,
+        ctx: &mut CallbackCtx<'local>,
+        event: &MotionEvent<'local>,
+    ) -> bool {
+        self.drain_tasks();
+        self.generic_motion(ctx, event)
+    }
+
+    fn on_hover_event<'local>(
+        &mut self,
+        ctx: &mut CallbackCtx<'local>,
+        event: &MotionEvent<'local>,
+    ) -> bool {
+        let action = event.action(&mut ctx.env);
+        let x = event.x(&mut ctx.env);
+        let y = event.y(&mut ctx.env);
+        let ui = self.state.android_state_mut();
+        if let Some(events) = ui
+            .access_adapter
+            .on_hover_event(&mut NullActionHandler, action, x, y)
+        {
+            ctx.push_dynamic_deferred_callback(move |env, view| {
+                raise_if_enabled(env, view, events);
+            });
+            true
+        } else {
+            self.drain_tasks();
+            self.generic_motion(ctx, event)
+        }
+    }
+
     fn on_focus_changed<'local>(
         &mut self,
         ctx: &mut CallbackCtx<'local>,
@@ -646,32 +584,10 @@ impl<State: AndroidAppState> ViewPeer for IrisViewPeer<State> {
         height: i32,
     ) {
         self.drain_tasks();
-        // The layout engine's own notion of the canvas size is separate
-        // from the wgpu surface's -- winit's backend sets it from
-        // `WindowEvent::Resized`, and there is no equivalent automatic
-        // trigger here, so this is the one place android-view's surface
-        // size has to be told to `UiRenderState` too. Missing this drew
-        // nothing but the clear colour: the widget tree laid out against
-        // whatever size `UiRenderState::new` starts at instead of the
-        // surface's real one.
-        //
-        // **Physical pixels, matching `AndroidRenderer`'s own
-        // `size()`/`resize()`/`new()`** -- `AndroidUiState::content_scale`'s
-        // field comment. This call sets `UiRenderState::output_size`, which
-        // every `rel`/`rest` length resolves against and every `abs`
-        // pixel-region compares to directly; a `dp(56)` height now folds
-        // in the density at `Len::apply_rest` time instead of this call
-        // dividing the whole window into a separate logical space, which
-        // is what used to make every `abs`-unit size (a fixed `.height(56)`
-        // in particular) mean something different from a `rest`-based one.
+        // The layout canvas and wgpu surface are separate and both use physical pixels.
         self.rsc.ui.resize((width as f32, height as f32));
 
-        // `AndroidRenderer::resize` only reconfigures the wgpu surface and
-        // rewrites the window uniform -- device, atlas, buffers and bind
-        // groups are untouched, so the glyph cache's coordinates stay
-        // valid. A genuinely new surface (after `surface_destroyed`, e.g.
-        // backgrounding) still goes through `AndroidRenderer::new` below,
-        // since `renderer` is `None` in that case.
+        // Resizing preserves GPU resources; recreating a destroyed surface does not.
         let already_live = self.state.android_state().renderer.is_some();
         log::info!(
             "iris surface: surface_changed {width}x{height} already_live={already_live} \
@@ -883,14 +799,7 @@ pub fn new_peer<'local, State: AndroidAppState>(
     let vm = env.get_java_vm().unwrap();
     let global_view = env.new_global_ref(&view.0).unwrap();
     let redraw: Arc<dyn RequestRedraw> = Arc::new(AndroidRedrawHandle::new(vm, global_view));
-    let (tasks, task_recv) = Tasks::init(redraw);
-    let mut rsc = AndroidRsc {
-        ui: Default::default(),
-        events: Default::default(),
-        tasks,
-        state: Default::default(),
-        _state: PhantomData,
-    };
+    let (mut rsc, task_recv) = AppRsc::new(redraw);
     rsc.ui.set_density(content_scale);
     let shared = Rc::new(RefCell::new(Shared::default()));
     let ui_state = AndroidUiState::new(shared.clone(), content_scale);