Struct WidgetRegistry 

pub struct WidgetRegistry { /* private fields */ }

Global registry of mounted widget panels.

Implementations

impl WidgetRegistry

pub fn new() -> Self

pub fn mount( &mut self, panel_id: PanelId, buffer_id: BufferId, spec: WidgetSpec, hits: Vec<HitArea>, instance_states: HashMap<String, WidgetInstanceState>, focus_key: String, tabbable: Vec<String>, ) -> Option<WidgetPanelState>

Mount or replace a panel. Returns the previous state if the panel was already mounted (the dispatcher may use this to detect re-mounts on the same id).

The wide parameter list is the price of WidgetPanelState being public — every field is plainly named at the call site rather than buried inside an opaque builder. The dispatcher always populates them all from one RenderOutput, so the apparent verbosity stays at the boundary.

pub fn update( &mut self, panel_id: PanelId, spec: WidgetSpec, hits: Vec<HitArea>, instance_states: HashMap<String, WidgetInstanceState>, focus_key: String, tabbable: Vec<String>, ) -> Result<BufferId, ()>

Replace the spec and rendered metadata on an already-mounted panel. Returns Ok(buffer_id) to render into, or Err(()) if no panel exists for that id (caller should drop the update — the plugin re-emitted after unmount). The unit error is sufficient: there’s exactly one failure mode and no payload to attach.

pub fn instance_states( &self, panel_id: PanelId, ) -> Option<&HashMap<String, WidgetInstanceState>>

Read-only access to the instance state for a panel — used by the dispatcher to thread previous scroll offsets / cursor positions into the next render so they persist.

pub fn focus_key(&self, panel_id: PanelId) -> Option<&str>

Read-only access to the previous render’s focus key.

pub fn set_focus_key(&mut self, panel_id: PanelId, key: String)

Set the focus key directly (used by widget_focus_advance and click-driven focus moves). Updates the in-place state; the next render reads it via focus_key().

pub fn set_list_scroll( &mut self, panel_id: PanelId, list_key: &str, scroll_offset: u32, visible: u32, ) -> Option<i32>

Host-driven scroll of a List widget (e.g. a scrollbar drag). Sets the list’s scroll_offset and, when the list has a live selection, clamps selected_index into the new visible window [scroll, scroll + visible) so the next render’s ensure-selected-visible doesn’t snap the thumb back.

Returns the post-clamp selected_index when the list has a selection that moved (so the caller can notify the plugin to keep its own selection mirror + preview in sync), else None.

pub fn update_side_effects( &mut self, panel_id: PanelId, hits: Vec<HitArea>, instance_states: HashMap<String, WidgetInstanceState>, focus_key: String, tabbable: Vec<String>, ) -> Result<BufferId, ()>

Update side-effects (hits, instance_states, focus_key, tabbable) without taking ownership of the spec. Used by rerender_widget_panel after an in-place spec mutation: the spec in the registry is already current (mutation helpers like append_tree_nodes_in_spec mutate it in place), so cloning it back through update() just to write the same value would waste a 5 000-node deep clone for every IPC.

pub fn buffer_and_spec_ref( &self, panel_id: PanelId, ) -> Option<(BufferId, &WidgetSpec)>

Borrow the current spec + return the buffer id. Companion to update_side_effects — render with the borrow and then write back only the side-effects, avoiding the deep clone of the spec that buffer_and_spec() does.

pub fn buffer_and_spec( &self, panel_id: PanelId, ) -> Option<(BufferId, WidgetSpec)>

Find the buffer and current spec for a panel — used by the dispatcher to re-render after a focus advance / activate command without the plugin needing to send an UpdateWidgetPanel.

pub fn unmount(&mut self, panel_id: PanelId) -> Option<BufferId>

Tear down a panel. Returns the buffer_id the panel was rendering into, so the caller can clear the buffer if it owns it.

pub fn get(&self, panel_id: PanelId) -> Option<&WidgetPanelState>

Read-only access to a panel’s current state.

pub fn get_mut(&mut self, panel_id: PanelId) -> Option<&mut WidgetPanelState>

Mutable access — used by WidgetCommand handlers that update widget instance state (e.g. TextInput value/cursor) directly without round-tripping through the plugin.

pub fn panel_ids(&self) -> Vec<PanelId>

All currently-mounted panel ids — useful for theme-change re-render passes (every panel re-renders against the new theme without plugin involvement).

pub fn panels_for_buffer(&self, buffer_id: BufferId) -> Vec<PanelId>

Panels rendering into buffer_id. Used by mouse-wheel routing to find which widget panel sits under the pointer.

pub fn hit_test( &self, buffer_id: BufferId, row: u32, col_byte: u32, ) -> Option<(PanelId, HitArea)>

Hit-test the given buffer-local position against every currently-mounted panel rendering into buffer_id. Returns the matching panel id and a clone of the hit area on a hit, None otherwise.

Linear scan: panel count is typically 1 per buffer; per-panel hit count is small (one per interactive widget). A spatial index would be over-engineering at this scale.

Trait Implementations

impl Debug for WidgetRegistry

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for WidgetRegistry

fn default() -> WidgetRegistry

Returns the “default value” for a type.