WIP: Start on accesskit integration

Cargo.lock

@@ -2,6 +2,34 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "accesskit"
+version = "0.12.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6cb10ed32c63247e4e39a8f42e8e30fb9442fbf7878c8e4a9849e7e381619bea"
+
+[[package]]
+name = "accesskit_consumer"
+version = "0.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9846654e84f26a31d269c0a8ea44fd8848319ee9cdf8908de18f51356f61f598"
+dependencies = [
+ "accesskit",
+]
+
+[[package]]
+name = "accesskit_macos"
+version = "0.11.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee4354e6f1a880a3a368fe6339fb4c1b94ccd2c8a053f6752abb09f4497758b3"
+dependencies = [
+ "accesskit",
+ "accesskit_consumer",
+ "icrate",
+ "objc2",
+ "once_cell",
+]
+
 [[package]]
 name = "activity_indicator"
 version = "0.1.0"
@@ -1457,6 +1485,25 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "block-sys"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ae85a0696e7ea3b835a453750bf002770776609115e6d25c6d2ff28a8200f7e7"
+dependencies = [
+ "objc-sys",
+]
+
+[[package]]
+name = "block2"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e58aa60e59d8dbfcc36138f5f18be5f24394d33b38b24f7fd0b1caa33095f22f"
+dependencies = [
+ "block-sys",
+ "objc2",
+]
+
 [[package]]
 name = "blocking"
 version = "1.3.1"
@@ -4070,6 +4117,8 @@ dependencies = [
 name = "gpui"
 version = "0.1.0"
 dependencies = [
+ "accesskit",
+ "accesskit_macos",
  "anyhow",
  "as-raw-xcb-connection",
  "ashpd",
@@ -4500,6 +4549,16 @@ dependencies = [
  "cc",
 ]
 
+[[package]]
+name = "icrate"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e286f4b975ac6c054971a0600a9b76438b332edace54bff79c71c9d3adfc9772"
+dependencies = [
+ "block2",
+ "objc2",
+]
+
 [[package]]
 name = "idna"
 version = "0.4.0"
@@ -6101,6 +6160,28 @@ dependencies = [
  "objc_exception",
 ]
 
+[[package]]
+name = "objc-sys"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c7c71324e4180d0899963fc83d9d241ac39e699609fc1025a850aadac8257459"
+
+[[package]]
+name = "objc2"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9a9c7f0d511a4ce26b078183179dca908171cfc69f88986fe36c5138e1834476"
+dependencies = [
+ "objc-sys",
+ "objc2-encode",
+]
+
+[[package]]
+name = "objc2-encode"
+version = "4.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2ff06a6505cde0766484f38d8479ac8e6d31c66fbc2d5492f65ca8c091456379"
+
 [[package]]
 name = "objc_exception"
 version = "0.1.2"

crates/gpui/Cargo.toml

@@ -68,6 +68,7 @@ usvg = { version = "0.14", features = [] }
 util.workspace = true
 uuid = { version = "1.1.2", features = ["v4"] }
 waker-fn = "1.1.0"
+accesskit = { version = "0.12" }
 
 [dev-dependencies]
 backtrace = "0.3"
@@ -93,6 +94,7 @@ log.workspace = true
 media.workspace = true
 metal = "0.21.0"
 objc = "0.2"
+accesskit_macos = "0.11.0"
 
 [target.'cfg(target_os = "linux")'.dependencies]
 flume = "0.11"

crates/gpui/src/access_kit.rs

@@ -0,0 +1,58 @@
+use std::hash::{Hash, Hasher};
+
+use collections::{hash_map::Entry, HashMap};
+
+use crate::{BorrowWindow, ElementContext, ElementId, GlobalElementId, WindowContext};
+
+pub type AccessKitState = HashMap<accesskit::NodeId, accesskit::NodeBuilder>;
+
+impl From<&GlobalElementId> for accesskit::NodeId {
+    fn from(value: &GlobalElementId) -> Self {
+        let mut hasher = std::hash::DefaultHasher::new();
+        value.0.hash(&mut hasher);
+        accesskit::NodeId(hasher.finish())
+    }
+}
+
+impl<'a> ElementContext<'a> {
+
+    // TODO: What's a good, useful signature for this? Need to expose this from the div as well.
+    fn accesskit_action(&mut self, id: impl Into<ElementId>, action: accesskit::Action, f: impl FnOnce(accesskit::ActionRequest)) {
+        self.with_element_id(Some(id), |cx| {
+            // Get the access kit actions from somewhere
+            // call f with the action request and cx
+            // egui impl:
+            //     let accesskit_id = id.accesskit_id();
+            //     self.events.iter().filter_map(move |event| {
+            //         if let Event::AccessKitActionRequest(request) = event {
+            //             if request.target == accesskit_id && request.action == action {
+            //                 return Some(request);
+            //             }
+            //         }
+            //         None
+            //     })
+
+        })
+    }
+
+    // TODO: Expose this through the div API
+    fn with_accesskit_node(&mut self, id: impl Into<ElementId>, f: impl FnOnce(&mut accesskit::NodeBuilder)) {
+        let id = id.into();
+        let window = self.window_mut();
+        let parent_id: accesskit::NodeId = (&window.element_id_stack).into();
+        self.with_element_id(Some(id), |cx| {
+            let window = cx.window_mut();
+            let this_id: accesskit::NodeId = (&window.element_id_stack).into();
+
+            window.next_frame.accesskit.as_mut().map(|nodes| {
+                if let Entry::Vacant(entry) = nodes.entry(this_id) {
+                    entry.insert(Default::default());
+                    let parent = nodes.get_mut(&parent_id).unwrap();
+                    parent.push_child(this_id);
+                }
+
+                f(nodes.get_mut(&this_id).unwrap());
+            })
+        });
+    }
+}

crates/gpui/src/app.rs

@@ -241,6 +241,7 @@ pub struct AppContext {
     pub(crate) quit_observers: SubscriberSet<(), QuitHandler>,
     pub(crate) layout_id_buffer: Vec<LayoutId>, // We recycle this memory across layout requests.
     pub(crate) propagate_event: bool,
+    pub(crate) screen_reader_enabled: bool,
 }
 
 impl AppContext {
@@ -299,6 +300,7 @@ impl AppContext {
                 quit_observers: SubscriberSet::new(),
                 layout_id_buffer: Default::default(),
                 propagate_event: true,
+                screen_reader_enabled: false,
             }),
         });
 
@@ -314,6 +316,7 @@ impl AppContext {
         app
     }
 
+
     /// Quit the application gracefully. Handlers registered with [`ModelContext::on_app_quit`]
     /// will be given 100ms to complete before exiting.
     pub fn shutdown(&mut self) {

crates/gpui/src/element.rs

@@ -38,9 +38,10 @@ use crate::{
     util::FluentBuilder, ArenaBox, AvailableSpace, Bounds, ElementContext, ElementId, LayoutId,
     Pixels, Point, Size, ViewContext, WindowContext, ELEMENT_ARENA,
 };
+use collections::FxHashSet;
 use derive_more::{Deref, DerefMut};
 pub(crate) use smallvec::SmallVec;
-use std::{any::Any, fmt::Debug, ops::DerefMut};
+use std::{any::Any, fmt::Debug, hash::{Hash, Hasher, SipHasher}, ops::DerefMut};
 
 /// Implemented by types that participate in laying out and painting the contents of a window.
 /// Elements form a tree and are laid out according to web-based layout rules, as implemented by Taffy.
@@ -222,7 +223,8 @@ impl<C: RenderOnce> IntoElement for Component<C> {
 
 /// A globally unique identifier for an element, used to track state across frames.
 #[derive(Deref, DerefMut, Default, Clone, Debug, Eq, PartialEq, Hash)]
-pub(crate) struct GlobalElementId(SmallVec<[ElementId; 32]>);
+pub(crate) struct GlobalElementId(pub(crate) SmallVec<[ElementId; 32]>);
+
 
 trait ElementObject {
     fn element_id(&self) -> Option<ElementId>;

crates/gpui/src/gpui.rs

@@ -67,6 +67,7 @@
 mod action;
 mod app;
 
+mod access_kit;
 mod arena;
 mod assets;
 mod color;

crates/gpui/src/platform/mac/window.rs

@@ -222,6 +222,22 @@ unsafe fn build_classes() {
             accepts_first_mouse as extern "C" fn(&Object, Sel, id) -> BOOL,
         );
 
+        // AccesKit integration poitns
+        decl.add_method(
+            sel!(accessibilityChildren),
+            accessibility_children as extern "C" fn(&mut Object, Sel) -> id,
+        );
+
+        decl.add_method(
+            sel!(accessibilityFocusedUIElement),
+            accessibility_focused as extern "C" fn(&mut Object, Sel) -> id,
+        );
+
+        decl.add_method(
+            sel!(accessibilityHitTest:),
+            accessibility_hit_test as extern "C" fn(&mut Object, Sel, NSPoint) -> id,
+        );
+
         decl.register()
     };
 }
@@ -343,6 +359,7 @@ struct MacWindowState {
     input_during_keydown: Option<SmallVec<[ImeInput; 1]>>,
     previous_keydown_inserted_text: Option<String>,
     external_files_dragged: bool,
+    accesskit: Option<accesskit_macos::Adapter>
 }
 
 impl MacWindowState {
@@ -467,6 +484,30 @@ impl MacWindowState {
             msg_send![self.native_window, convertPointToScreen: point]
         }
     }
+
+    fn get_accesskit_adapter(&mut self) -> &accesskit_macos::Adapter {
+        self.accesskit.get_or_insert_with(|| {
+            fn handler() -> (accesskit::TreeUpdate, bool) {
+                todo!()
+            }
+
+            let (initial_state, focused) = handler();// self.handler.accesskit_tree();
+
+            struct Handler {}
+            impl accesskit::ActionHandler for Handler {
+                fn do_action(&mut self, _action: accesskit::ActionRequest) {
+                    todo!();
+                }
+            }
+
+            let action_handler = Box::new(Handler {});
+
+            // SAFETY: The view pointer is based on a valid borrowed reference
+            // to the view.
+            unsafe { accesskit_macos::Adapter::new(self.native_view.as_ptr() as *mut _, initial_state, self.is_active, action_handler) }
+        })
+    }
+
 }
 
 unsafe impl Send for MacWindowState {}
@@ -541,6 +582,8 @@ impl MacWindow {
             let native_view = NSView::init(native_view);
             assert!(!native_view.is_null());
 
+            // let accesskit_adapter = accesskit_macos::Adapter::new(native_view, accesskit::TreeUpdate { nodes: Default::default(), tree: Default::default(), focus: accesskit::NodeId(0) }, false, action_handler);
+
             let window = Self(Arc::new(Mutex::new(MacWindowState {
                 handle,
                 executor,
@@ -570,6 +613,7 @@ impl MacWindow {
                 input_during_keydown: None,
                 previous_keydown_inserted_text: None,
                 external_files_dragged: false,
+                accesskit: None,
             })));
 
             (*native_window).set_ivar(
@@ -1737,6 +1781,36 @@ extern "C" fn accepts_first_mouse(this: &Object, _: Sel, _: id) -> BOOL {
     }
 }
 
+extern "C" fn accessibility_children(this: &mut Object, _: Sel) -> id {
+    unsafe {
+        let state = get_window_state(this);
+        let mut lock = state.as_ref().lock();
+        let adapter = lock.get_accesskit_adapter();
+        adapter.view_children() as *mut _
+    }
+}
+extern "C" fn accessibility_focused(this: &mut Object, _: Sel) -> id {
+    unsafe {
+        let state = get_window_state(this);
+        let mut lock = state.as_ref().lock();
+        let adapter = lock.get_accesskit_adapter();
+        adapter.focus() as *mut _
+    }
+}
+extern "C" fn accessibility_hit_test(this: &mut Object, _: Sel, point: NSPoint) -> id {
+    unsafe {
+        let state = get_window_state(this);
+        let mut lock = state.as_ref().lock();
+        let adapter = lock.get_accesskit_adapter();
+
+        let point = accesskit_macos::NSPoint {
+            x: point.x,
+            y: point.y,
+        };
+        adapter.hit_test(point) as *mut _
+    }
+}
+
 extern "C" fn dragging_entered(this: &Object, _: Sel, dragging_info: id) -> NSDragOperation {
     let window_state = unsafe { get_window_state(this) };
     if send_new_event(&window_state, {

crates/gpui/src/window.rs

@@ -1,13 +1,5 @@
 use crate::{
-    px, size, transparent_black, Action, AnyDrag, AnyView, AppContext, Arena, AsyncWindowContext,
+    px, size, transparent_black, Action, AnyDrag, AnyView, AppContext, Arena, AsyncWindowContext, AvailableSpace, Bounds, Context, Corners, CursorStyle, DispatchActionListener, DispatchNodeId, DispatchTree, DisplayId, Edges, Effect, Entity, EntityId, EventEmitter, FileDropEvent, Flatten, Global, GlobalElementId, Hsla, IntoElement, KeyBinding, KeyContext, KeyDownEvent, KeyMatch, KeymatchResult, Keystroke, KeystrokeEvent, Model, ModelContext, Modifiers, MouseButton, MouseMoveEvent, MouseUpEvent, Pixels, PlatformAtlas, PlatformDisplay, PlatformInput, PlatformWindow, Point, PromptLevel, Render, ScaledPixels, SharedString, Size, SubscriberSet, Subscription, TaffyLayoutEngine, Task, View, VisualContext, WeakView, WindowAppearance, WindowBounds, WindowOptions, WindowTextSystem
-    AvailableSpace, Bounds, Context, Corners, CursorStyle, DispatchActionListener, DispatchNodeId,
-    DispatchTree, DisplayId, Edges, Effect, Entity, EntityId, EventEmitter, FileDropEvent, Flatten,
-    Global, GlobalElementId, Hsla, KeyBinding, KeyContext, KeyDownEvent, KeyMatch, KeymatchResult,
-    Keystroke, KeystrokeEvent, Model, ModelContext, Modifiers, MouseButton, MouseMoveEvent,
-    MouseUpEvent, Pixels, PlatformAtlas, PlatformDisplay, PlatformInput, PlatformWindow, Point,
-    PromptLevel, Render, ScaledPixels, SharedString, Size, SubscriberSet, Subscription,
-    TaffyLayoutEngine, Task, View, VisualContext, WeakView, WindowAppearance, WindowBounds,
-    WindowOptions, WindowTextSystem,
 };
 use anyhow::{anyhow, Context as _, Result};
 use collections::FxHashSet;
@@ -17,20 +9,10 @@ use parking_lot::RwLock;
 use slotmap::SlotMap;
 use smallvec::SmallVec;
 use std::{
-    any::{Any, TypeId},
+    any::{Any, TypeId}, borrow::{Borrow, BorrowMut}, cell::{Cell, RefCell}, collections::HashMap, fmt::{Debug, Display}, future::Future, hash::{Hash, Hasher}, marker::PhantomData, mem, rc::Rc, sync::{
-    borrow::{Borrow, BorrowMut},
-    cell::{Cell, RefCell},
-    fmt::{Debug, Display},
-    future::Future,
-    hash::{Hash, Hasher},
-    marker::PhantomData,
-    mem,
-    rc::Rc,
-    sync::{
         atomic::{AtomicUsize, Ordering::SeqCst},
         Arc,
-    },
+    }, time::{Duration, Instant}
-    time::{Duration, Instant},
 };
 use util::{measure, ResultExt};
 
@@ -950,6 +932,7 @@ impl<'a> WindowContext<'a> {
         }
 
         let root_view = self.window.root_view.take().unwrap();
+
         self.with_element_context(|cx| {
             cx.with_z_index(0, |cx| {
                 cx.with_key_dispatch(Some(KeyContext::default()), None, |_, cx| {

crates/gpui/src/window/element_cx.rs

@@ -29,14 +29,7 @@ use smallvec::SmallVec;
 use util::post_inc;
 
 use crate::{
-    prelude::*, size, AnyTooltip, AppContext, AvailableSpace, Bounds, BoxShadow, ContentMask,
+    access_kit::AccessKitState, prelude::*, size, AnyTooltip, AppContext, AvailableSpace, Bounds, BoxShadow, ContentMask, Corners, CursorStyle, DevicePixels, DispatchPhase, DispatchTree, ElementId, ElementStateBox, EntityId, FocusHandle, FocusId, FontId, GlobalElementId, GlyphId, Hsla, ImageData, InputHandler, IsZero, KeyContext, KeyEvent, LayoutId, MonochromeSprite, MouseEvent, PaintQuad, Path, Pixels, PlatformInputHandler, Point, PolychromeSprite, Quad, RenderGlyphParams, RenderImageParams, RenderSvgParams, Scene, Shadow, SharedString, Size, StackingContext, StackingOrder, StrikethroughStyle, Style, TextStyleRefinement, Underline, UnderlineStyle, Window, WindowContext, SUBPIXEL_VARIANTS
-    Corners, CursorStyle, DevicePixels, DispatchPhase, DispatchTree, ElementId, ElementStateBox,
-    EntityId, FocusHandle, FocusId, FontId, GlobalElementId, GlyphId, Hsla, ImageData,
-    InputHandler, IsZero, KeyContext, KeyEvent, LayoutId, MonochromeSprite, MouseEvent, PaintQuad,
-    Path, Pixels, PlatformInputHandler, Point, PolychromeSprite, Quad, RenderGlyphParams,
-    RenderImageParams, RenderSvgParams, Scene, Shadow, SharedString, Size, StackingContext,
-    StackingOrder, StrikethroughStyle, Style, TextStyleRefinement, Underline, UnderlineStyle,
-    Window, WindowContext, SUBPIXEL_VARIANTS,
 };
 
 type AnyMouseListener = Box<dyn FnMut(&dyn Any, DispatchPhase, &mut ElementContext) + 'static>;
@@ -70,6 +63,7 @@ pub(crate) struct Frame {
     pub(crate) requested_cursor_style: Option<CursorStyle>,
     pub(crate) view_stack: Vec<EntityId>,
     pub(crate) reused_views: FxHashSet<EntityId>,
+    pub(crate) accesskit: Option<AccessKitState>,
 
     #[cfg(any(test, feature = "test-support"))]
     pub(crate) debug_bounds: FxHashMap<String, Bounds<Pixels>>,
@@ -96,6 +90,7 @@ impl Frame {
             requested_cursor_style: None,
             view_stack: Vec::new(),
             reused_views: FxHashSet::default(),
+            accesskit: None,
 
             #[cfg(any(test, feature = "test-support"))]
             debug_bounds: FxHashMap::default(),
@@ -386,6 +381,7 @@ impl<'a> ElementContext<'a> {
         }
     }
 
+
     /// Updates the cursor style at the platform level.
     pub fn set_cursor_style(&mut self, style: CursorStyle) {
         let view_id = self.parent_view_id();