picker.rs

  1mod head;
  2pub mod highlighted_match_with_paths;
  3pub mod popover_menu;
  4
  5use anyhow::Result;
  6use editor::{
  7    Editor, SelectionEffects,
  8    actions::{MoveDown, MoveUp},
  9    scroll::Autoscroll,
 10};
 11use gpui::{
 12    Action, AnyElement, App, ClickEvent, Context, DismissEvent, Entity, EventEmitter, FocusHandle,
 13    Focusable, Length, ListSizingBehavior, ListState, MouseButton, MouseUpEvent, Render,
 14    ScrollStrategy, Stateful, Task, UniformListScrollHandle, Window, actions, div, list,
 15    prelude::*, uniform_list,
 16};
 17use head::Head;
 18use schemars::JsonSchema;
 19use serde::Deserialize;
 20use std::{ops::Range, sync::Arc, time::Duration};
 21use ui::{
 22    Color, Divider, Label, ListItem, ListItemSpacing, Scrollbar, ScrollbarState, prelude::*, v_flex,
 23};
 24use util::ResultExt;
 25use workspace::ModalView;
 26
 27enum ElementContainer {
 28    List(ListState),
 29    UniformList(UniformListScrollHandle),
 30}
 31
 32pub enum Direction {
 33    Up,
 34    Down,
 35}
 36
 37actions!(picker, [ConfirmCompletion]);
 38
 39/// ConfirmInput is an alternative editor action which - instead of selecting active picker entry - treats pickers editor input literally,
 40/// performing some kind of action on it.
 41#[derive(Clone, PartialEq, Deserialize, JsonSchema, Default, Action)]
 42#[action(namespace = picker)]
 43#[serde(deny_unknown_fields)]
 44pub struct ConfirmInput {
 45    pub secondary: bool,
 46}
 47
 48struct PendingUpdateMatches {
 49    delegate_update_matches: Option<Task<()>>,
 50    _task: Task<Result<()>>,
 51}
 52
 53pub struct Picker<D: PickerDelegate> {
 54    pub delegate: D,
 55    element_container: ElementContainer,
 56    head: Head,
 57    pending_update_matches: Option<PendingUpdateMatches>,
 58    confirm_on_update: Option<bool>,
 59    width: Option<Length>,
 60    widest_item: Option<usize>,
 61    max_height: Option<Length>,
 62    focus_handle: FocusHandle,
 63    /// An external control to display a scrollbar in the `Picker`.
 64    show_scrollbar: bool,
 65    /// An internal state that controls whether to show the scrollbar based on the user's focus.
 66    scrollbar_visibility: bool,
 67    scrollbar_state: ScrollbarState,
 68    hide_scrollbar_task: Option<Task<()>>,
 69    /// Whether the `Picker` is rendered as a self-contained modal.
 70    ///
 71    /// Set this to `false` when rendering the `Picker` as part of a larger modal.
 72    is_modal: bool,
 73}
 74
 75#[derive(Debug, Default, Clone, Copy, PartialEq)]
 76pub enum PickerEditorPosition {
 77    #[default]
 78    /// Render the editor at the start of the picker. Usually the top
 79    Start,
 80    /// Render the editor at the end of the picker. Usually the bottom
 81    End,
 82}
 83
 84pub trait PickerDelegate: Sized + 'static {
 85    type ListItem: IntoElement;
 86
 87    fn match_count(&self) -> usize;
 88    fn selected_index(&self) -> usize;
 89    fn separators_after_indices(&self) -> Vec<usize> {
 90        Vec::new()
 91    }
 92    fn set_selected_index(
 93        &mut self,
 94        ix: usize,
 95        window: &mut Window,
 96        cx: &mut Context<Picker<Self>>,
 97    );
 98    fn can_select(
 99        &mut self,
100        _ix: usize,
101        _window: &mut Window,
102        _cx: &mut Context<Picker<Self>>,
103    ) -> bool {
104        true
105    }
106
107    // Allows binding some optional effect to when the selection changes.
108    fn selected_index_changed(
109        &self,
110        _ix: usize,
111        _window: &mut Window,
112        _cx: &mut Context<Picker<Self>>,
113    ) -> Option<Box<dyn Fn(&mut Window, &mut App) + 'static>> {
114        None
115    }
116    fn placeholder_text(&self, _window: &mut Window, _cx: &mut App) -> Arc<str>;
117    fn no_matches_text(&self, _window: &mut Window, _cx: &mut App) -> Option<SharedString> {
118        Some("No matches".into())
119    }
120    fn update_matches(
121        &mut self,
122        query: String,
123        window: &mut Window,
124        cx: &mut Context<Picker<Self>>,
125    ) -> Task<()>;
126
127    // Delegates that support this method (e.g. the CommandPalette) can chose to block on any background
128    // work for up to `duration` to try and get a result synchronously.
129    // This avoids a flash of an empty command-palette on cmd-shift-p, and lets workspace::SendKeystrokes
130    // mostly work when dismissing a palette.
131    fn finalize_update_matches(
132        &mut self,
133        _query: String,
134        _duration: Duration,
135        _window: &mut Window,
136        _cx: &mut Context<Picker<Self>>,
137    ) -> bool {
138        false
139    }
140
141    /// Override if you want to have <enter> update the query instead of confirming.
142    fn confirm_update_query(
143        &mut self,
144        _window: &mut Window,
145        _cx: &mut Context<Picker<Self>>,
146    ) -> Option<String> {
147        None
148    }
149    fn confirm(&mut self, secondary: bool, window: &mut Window, cx: &mut Context<Picker<Self>>);
150    /// Instead of interacting with currently selected entry, treats editor input literally,
151    /// performing some kind of action on it.
152    fn confirm_input(
153        &mut self,
154        _secondary: bool,
155        _window: &mut Window,
156        _: &mut Context<Picker<Self>>,
157    ) {
158    }
159    fn dismissed(&mut self, window: &mut Window, cx: &mut Context<Picker<Self>>);
160    fn should_dismiss(&self) -> bool {
161        true
162    }
163    fn confirm_completion(
164        &mut self,
165        _query: String,
166        _window: &mut Window,
167        _: &mut Context<Picker<Self>>,
168    ) -> Option<String> {
169        None
170    }
171
172    fn editor_position(&self) -> PickerEditorPosition {
173        PickerEditorPosition::default()
174    }
175
176    fn render_editor(
177        &self,
178        editor: &Entity<Editor>,
179        _window: &mut Window,
180        _cx: &mut Context<Picker<Self>>,
181    ) -> Div {
182        v_flex()
183            .when(
184                self.editor_position() == PickerEditorPosition::End,
185                |this| this.child(Divider::horizontal()),
186            )
187            .child(
188                h_flex()
189                    .overflow_hidden()
190                    .flex_none()
191                    .h_9()
192                    .px_2p5()
193                    .child(editor.clone()),
194            )
195            .when(
196                self.editor_position() == PickerEditorPosition::Start,
197                |this| this.child(Divider::horizontal()),
198            )
199    }
200
201    fn render_match(
202        &self,
203        ix: usize,
204        selected: bool,
205        window: &mut Window,
206        cx: &mut Context<Picker<Self>>,
207    ) -> Option<Self::ListItem>;
208
209    fn render_header(
210        &self,
211        _window: &mut Window,
212        _: &mut Context<Picker<Self>>,
213    ) -> Option<AnyElement> {
214        None
215    }
216
217    fn render_footer(
218        &self,
219        _window: &mut Window,
220        _: &mut Context<Picker<Self>>,
221    ) -> Option<AnyElement> {
222        None
223    }
224}
225
226impl<D: PickerDelegate> Focusable for Picker<D> {
227    fn focus_handle(&self, cx: &App) -> FocusHandle {
228        match &self.head {
229            Head::Editor(editor) => editor.focus_handle(cx),
230            Head::Empty(head) => head.focus_handle(cx),
231        }
232    }
233}
234
235#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Copy)]
236enum ContainerKind {
237    List,
238    UniformList,
239}
240
241impl<D: PickerDelegate> Picker<D> {
242    /// A picker, which displays its matches using `gpui::uniform_list`, all matches should have the same height.
243    /// The picker allows the user to perform search items by text.
244    /// If `PickerDelegate::render_match` can return items with different heights, use `Picker::list`.
245    pub fn uniform_list(delegate: D, window: &mut Window, cx: &mut Context<Self>) -> Self {
246        let head = Head::editor(
247            delegate.placeholder_text(window, cx),
248            Self::on_input_editor_event,
249            window,
250            cx,
251        );
252
253        Self::new(delegate, ContainerKind::UniformList, head, window, cx)
254    }
255
256    /// A picker, which displays its matches using `gpui::uniform_list`, all matches should have the same height.
257    /// If `PickerDelegate::render_match` can return items with different heights, use `Picker::list`.
258    pub fn nonsearchable_uniform_list(
259        delegate: D,
260        window: &mut Window,
261        cx: &mut Context<Self>,
262    ) -> Self {
263        let head = Head::empty(Self::on_empty_head_blur, window, cx);
264
265        Self::new(delegate, ContainerKind::UniformList, head, window, cx)
266    }
267
268    /// A picker, which displays its matches using `gpui::list`, matches can have different heights.
269    /// The picker allows the user to perform search items by text.
270    /// If `PickerDelegate::render_match` only returns items with the same height, use `Picker::uniform_list` as its implementation is optimized for that.
271    pub fn list(delegate: D, window: &mut Window, cx: &mut Context<Self>) -> Self {
272        let head = Head::editor(
273            delegate.placeholder_text(window, cx),
274            Self::on_input_editor_event,
275            window,
276            cx,
277        );
278
279        Self::new(delegate, ContainerKind::List, head, window, cx)
280    }
281
282    fn new(
283        delegate: D,
284        container: ContainerKind,
285        head: Head,
286        window: &mut Window,
287        cx: &mut Context<Self>,
288    ) -> Self {
289        let element_container = Self::create_element_container(container, cx);
290        let scrollbar_state = match &element_container {
291            ElementContainer::UniformList(scroll_handle) => {
292                ScrollbarState::new(scroll_handle.clone())
293            }
294            ElementContainer::List(state) => ScrollbarState::new(state.clone()),
295        };
296        let focus_handle = cx.focus_handle();
297        let mut this = Self {
298            delegate,
299            head,
300            element_container,
301            pending_update_matches: None,
302            confirm_on_update: None,
303            width: None,
304            widest_item: None,
305            max_height: Some(rems(18.).into()),
306            focus_handle,
307            show_scrollbar: false,
308            scrollbar_visibility: true,
309            scrollbar_state,
310            is_modal: true,
311            hide_scrollbar_task: None,
312        };
313        this.update_matches("".to_string(), window, cx);
314        // give the delegate 4ms to render the first set of suggestions.
315        this.delegate
316            .finalize_update_matches("".to_string(), Duration::from_millis(4), window, cx);
317        this
318    }
319
320    fn create_element_container(
321        container: ContainerKind,
322        cx: &mut Context<Self>,
323    ) -> ElementContainer {
324        match container {
325            ContainerKind::UniformList => {
326                ElementContainer::UniformList(UniformListScrollHandle::new())
327            }
328            ContainerKind::List => {
329                let entity = cx.entity().downgrade();
330                ElementContainer::List(ListState::new(
331                    0,
332                    gpui::ListAlignment::Top,
333                    px(1000.),
334                    move |ix, window, cx| {
335                        entity
336                            .upgrade()
337                            .map(|entity| {
338                                entity.update(cx, |this, cx| {
339                                    this.render_element(window, cx, ix).into_any_element()
340                                })
341                            })
342                            .unwrap_or_else(|| div().into_any_element())
343                    },
344                ))
345            }
346        }
347    }
348
349    pub fn width(mut self, width: impl Into<gpui::Length>) -> Self {
350        self.width = Some(width.into());
351        self
352    }
353
354    pub fn widest_item(mut self, ix: Option<usize>) -> Self {
355        self.widest_item = ix;
356        self
357    }
358
359    pub fn max_height(mut self, max_height: Option<gpui::Length>) -> Self {
360        self.max_height = max_height;
361        self
362    }
363
364    pub fn show_scrollbar(mut self, show_scrollbar: bool) -> Self {
365        self.show_scrollbar = show_scrollbar;
366        self
367    }
368
369    pub fn modal(mut self, modal: bool) -> Self {
370        self.is_modal = modal;
371        self
372    }
373
374    pub fn focus(&self, window: &mut Window, cx: &mut App) {
375        self.focus_handle(cx).focus(window);
376    }
377
378    /// Handles the selecting an index, and passing the change to the delegate.
379    /// If `fallback_direction` is set to `None`, the index will not be selected
380    /// if the element at that index cannot be selected.
381    /// If `fallback_direction` is set to
382    /// `Some(..)`, the next selectable element will be selected in the
383    /// specified direction (Down or Up), cycling through all elements until
384    /// finding one that can be selected or returning if there are no selectable elements.
385    /// If `scroll_to_index` is true, the new selected index will be scrolled into
386    /// view.
387    ///
388    /// If some effect is bound to `selected_index_changed`, it will be executed.
389    pub fn set_selected_index(
390        &mut self,
391        mut ix: usize,
392        fallback_direction: Option<Direction>,
393        scroll_to_index: bool,
394        window: &mut Window,
395        cx: &mut Context<Self>,
396    ) {
397        let match_count = self.delegate.match_count();
398        if match_count == 0 {
399            return;
400        }
401
402        if let Some(bias) = fallback_direction {
403            let mut curr_ix = ix;
404            while !self.delegate.can_select(curr_ix, window, cx) {
405                curr_ix = match bias {
406                    Direction::Down => {
407                        if curr_ix == match_count - 1 {
408                            0
409                        } else {
410                            curr_ix + 1
411                        }
412                    }
413                    Direction::Up => {
414                        if curr_ix == 0 {
415                            match_count - 1
416                        } else {
417                            curr_ix - 1
418                        }
419                    }
420                };
421                // There is no item that can be selected
422                if ix == curr_ix {
423                    return;
424                }
425            }
426            ix = curr_ix;
427        } else if !self.delegate.can_select(ix, window, cx) {
428            return;
429        }
430
431        let previous_index = self.delegate.selected_index();
432        self.delegate.set_selected_index(ix, window, cx);
433        let current_index = self.delegate.selected_index();
434
435        if previous_index != current_index {
436            if let Some(action) = self.delegate.selected_index_changed(ix, window, cx) {
437                action(window, cx);
438            }
439            if scroll_to_index {
440                self.scroll_to_item_index(ix);
441            }
442        }
443    }
444
445    pub fn select_next(
446        &mut self,
447        _: &menu::SelectNext,
448        window: &mut Window,
449        cx: &mut Context<Self>,
450    ) {
451        let count = self.delegate.match_count();
452        if count > 0 {
453            let index = self.delegate.selected_index();
454            let ix = if index == count - 1 { 0 } else { index + 1 };
455            self.set_selected_index(ix, Some(Direction::Down), true, window, cx);
456            cx.notify();
457        }
458    }
459
460    pub fn editor_move_up(&mut self, _: &MoveUp, window: &mut Window, cx: &mut Context<Self>) {
461        self.select_previous(&Default::default(), window, cx);
462    }
463
464    fn select_previous(
465        &mut self,
466        _: &menu::SelectPrevious,
467        window: &mut Window,
468        cx: &mut Context<Self>,
469    ) {
470        let count = self.delegate.match_count();
471        if count > 0 {
472            let index = self.delegate.selected_index();
473            let ix = if index == 0 { count - 1 } else { index - 1 };
474            self.set_selected_index(ix, Some(Direction::Up), true, window, cx);
475            cx.notify();
476        }
477    }
478
479    pub fn editor_move_down(&mut self, _: &MoveDown, window: &mut Window, cx: &mut Context<Self>) {
480        self.select_next(&Default::default(), window, cx);
481    }
482
483    pub fn select_first(
484        &mut self,
485        _: &menu::SelectFirst,
486        window: &mut Window,
487        cx: &mut Context<Self>,
488    ) {
489        let count = self.delegate.match_count();
490        if count > 0 {
491            self.set_selected_index(0, Some(Direction::Down), true, window, cx);
492            cx.notify();
493        }
494    }
495
496    fn select_last(&mut self, _: &menu::SelectLast, window: &mut Window, cx: &mut Context<Self>) {
497        let count = self.delegate.match_count();
498        if count > 0 {
499            self.set_selected_index(count - 1, Some(Direction::Up), true, window, cx);
500            cx.notify();
501        }
502    }
503
504    pub fn cycle_selection(&mut self, window: &mut Window, cx: &mut Context<Self>) {
505        let count = self.delegate.match_count();
506        let index = self.delegate.selected_index();
507        let new_index = if index + 1 == count { 0 } else { index + 1 };
508        self.set_selected_index(new_index, Some(Direction::Down), true, window, cx);
509        cx.notify();
510    }
511
512    pub fn cancel(&mut self, _: &menu::Cancel, window: &mut Window, cx: &mut Context<Self>) {
513        if self.delegate.should_dismiss() {
514            self.delegate.dismissed(window, cx);
515            cx.emit(DismissEvent);
516        }
517    }
518
519    fn confirm(&mut self, _: &menu::Confirm, window: &mut Window, cx: &mut Context<Self>) {
520        if self.pending_update_matches.is_some()
521            && !self.delegate.finalize_update_matches(
522                self.query(cx),
523                Duration::from_millis(16),
524                window,
525                cx,
526            )
527        {
528            self.confirm_on_update = Some(false)
529        } else {
530            self.pending_update_matches.take();
531            self.do_confirm(false, window, cx);
532        }
533    }
534
535    fn secondary_confirm(
536        &mut self,
537        _: &menu::SecondaryConfirm,
538        window: &mut Window,
539        cx: &mut Context<Self>,
540    ) {
541        if self.pending_update_matches.is_some()
542            && !self.delegate.finalize_update_matches(
543                self.query(cx),
544                Duration::from_millis(16),
545                window,
546                cx,
547            )
548        {
549            self.confirm_on_update = Some(true)
550        } else {
551            self.do_confirm(true, window, cx);
552        }
553    }
554
555    fn confirm_input(&mut self, input: &ConfirmInput, window: &mut Window, cx: &mut Context<Self>) {
556        self.delegate.confirm_input(input.secondary, window, cx);
557    }
558
559    fn confirm_completion(
560        &mut self,
561        _: &ConfirmCompletion,
562        window: &mut Window,
563        cx: &mut Context<Self>,
564    ) {
565        if let Some(new_query) = self.delegate.confirm_completion(self.query(cx), window, cx) {
566            self.set_query(new_query, window, cx);
567        } else {
568            cx.propagate()
569        }
570    }
571
572    fn handle_click(
573        &mut self,
574        ix: usize,
575        secondary: bool,
576        window: &mut Window,
577        cx: &mut Context<Self>,
578    ) {
579        cx.stop_propagation();
580        window.prevent_default();
581        self.set_selected_index(ix, None, false, window, cx);
582        self.do_confirm(secondary, window, cx)
583    }
584
585    fn do_confirm(&mut self, secondary: bool, window: &mut Window, cx: &mut Context<Self>) {
586        if let Some(update_query) = self.delegate.confirm_update_query(window, cx) {
587            self.set_query(update_query, window, cx);
588            self.set_selected_index(0, Some(Direction::Down), false, window, cx);
589        } else {
590            self.delegate.confirm(secondary, window, cx)
591        }
592    }
593
594    fn on_input_editor_event(
595        &mut self,
596        _: &Entity<Editor>,
597        event: &editor::EditorEvent,
598        window: &mut Window,
599        cx: &mut Context<Self>,
600    ) {
601        let Head::Editor(editor) = &self.head else {
602            panic!("unexpected call");
603        };
604        match event {
605            editor::EditorEvent::BufferEdited => {
606                let query = editor.read(cx).text(cx);
607                self.update_matches(query, window, cx);
608            }
609            editor::EditorEvent::Blurred => {
610                if self.is_modal {
611                    self.cancel(&menu::Cancel, window, cx);
612                }
613            }
614            _ => {}
615        }
616    }
617
618    fn on_empty_head_blur(&mut self, window: &mut Window, cx: &mut Context<Self>) {
619        let Head::Empty(_) = &self.head else {
620            panic!("unexpected call");
621        };
622        self.cancel(&menu::Cancel, window, cx);
623    }
624
625    pub fn refresh_placeholder(&mut self, window: &mut Window, cx: &mut App) {
626        match &self.head {
627            Head::Editor(editor) => {
628                let placeholder = self.delegate.placeholder_text(window, cx);
629                editor.update(cx, |editor, cx| {
630                    editor.set_placeholder_text(placeholder, cx);
631                    cx.notify();
632                });
633            }
634            Head::Empty(_) => {}
635        }
636    }
637
638    pub fn refresh(&mut self, window: &mut Window, cx: &mut Context<Self>) {
639        let query = self.query(cx);
640        self.update_matches(query, window, cx);
641    }
642
643    pub fn update_matches(&mut self, query: String, window: &mut Window, cx: &mut Context<Self>) {
644        let delegate_pending_update_matches = self.delegate.update_matches(query, window, cx);
645
646        self.matches_updated(window, cx);
647        // This struct ensures that we can synchronously drop the task returned by the
648        // delegate's `update_matches` method and the task that the picker is spawning.
649        // If we simply capture the delegate's task into the picker's task, when the picker's
650        // task gets synchronously dropped, the delegate's task would keep running until
651        // the picker's task has a chance of being scheduled, because dropping a task happens
652        // asynchronously.
653        self.pending_update_matches = Some(PendingUpdateMatches {
654            delegate_update_matches: Some(delegate_pending_update_matches),
655            _task: cx.spawn_in(window, async move |this, cx| {
656                let delegate_pending_update_matches = this.update(cx, |this, _| {
657                    this.pending_update_matches
658                        .as_mut()
659                        .unwrap()
660                        .delegate_update_matches
661                        .take()
662                        .unwrap()
663                })?;
664                delegate_pending_update_matches.await;
665                this.update_in(cx, |this, window, cx| {
666                    this.matches_updated(window, cx);
667                })
668            }),
669        });
670    }
671
672    fn matches_updated(&mut self, window: &mut Window, cx: &mut Context<Self>) {
673        if let ElementContainer::List(state) = &mut self.element_container {
674            state.reset(self.delegate.match_count());
675        }
676
677        let index = self.delegate.selected_index();
678        self.scroll_to_item_index(index);
679        self.pending_update_matches = None;
680        if let Some(secondary) = self.confirm_on_update.take() {
681            self.do_confirm(secondary, window, cx);
682        }
683        cx.notify();
684    }
685
686    pub fn query(&self, cx: &App) -> String {
687        match &self.head {
688            Head::Editor(editor) => editor.read(cx).text(cx),
689            Head::Empty(_) => "".to_string(),
690        }
691    }
692
693    pub fn set_query(&self, query: impl Into<Arc<str>>, window: &mut Window, cx: &mut App) {
694        if let Head::Editor(editor) = &self.head {
695            editor.update(cx, |editor, cx| {
696                editor.set_text(query, window, cx);
697                let editor_offset = editor.buffer().read(cx).len(cx);
698                editor.change_selections(
699                    SelectionEffects::scroll(Autoscroll::Next),
700                    window,
701                    cx,
702                    |s| s.select_ranges(Some(editor_offset..editor_offset)),
703                );
704            });
705        }
706    }
707
708    fn scroll_to_item_index(&mut self, ix: usize) {
709        match &mut self.element_container {
710            ElementContainer::List(state) => state.scroll_to_reveal_item(ix),
711            ElementContainer::UniformList(scroll_handle) => {
712                scroll_handle.scroll_to_item(ix, ScrollStrategy::Top)
713            }
714        }
715    }
716
717    fn render_element(
718        &self,
719        window: &mut Window,
720        cx: &mut Context<Self>,
721        ix: usize,
722    ) -> impl IntoElement + use<D> {
723        div()
724            .id(("item", ix))
725            .cursor_pointer()
726            .on_click(cx.listener(move |this, event: &ClickEvent, window, cx| {
727                this.handle_click(ix, event.modifiers().secondary(), window, cx)
728            }))
729            // As of this writing, GPUI intercepts `ctrl-[mouse-event]`s on macOS
730            // and produces right mouse button events. This matches platforms norms
731            // but means that UIs which depend on holding ctrl down (such as the tab
732            // switcher) can't be clicked on. Hence, this handler.
733            .on_mouse_up(
734                MouseButton::Right,
735                cx.listener(move |this, event: &MouseUpEvent, window, cx| {
736                    // We specifically want to use the platform key here, as
737                    // ctrl will already be held down for the tab switcher.
738                    this.handle_click(ix, event.modifiers.platform, window, cx)
739                }),
740            )
741            .children(self.delegate.render_match(
742                ix,
743                ix == self.delegate.selected_index(),
744                window,
745                cx,
746            ))
747            .when(
748                self.delegate.separators_after_indices().contains(&ix),
749                |picker| {
750                    picker
751                        .border_color(cx.theme().colors().border_variant)
752                        .border_b_1()
753                        .py(px(-1.0))
754                },
755            )
756    }
757
758    fn render_element_container(&self, cx: &mut Context<Self>) -> impl IntoElement {
759        let sizing_behavior = if self.max_height.is_some() {
760            ListSizingBehavior::Infer
761        } else {
762            ListSizingBehavior::Auto
763        };
764
765        match &self.element_container {
766            ElementContainer::UniformList(scroll_handle) => uniform_list(
767                "candidates",
768                self.delegate.match_count(),
769                cx.processor(move |picker, visible_range: Range<usize>, window, cx| {
770                    visible_range
771                        .map(|ix| picker.render_element(window, cx, ix))
772                        .collect()
773                }),
774            )
775            .with_sizing_behavior(sizing_behavior)
776            .when_some(self.widest_item, |el, widest_item| {
777                el.with_width_from_item(Some(widest_item))
778            })
779            .flex_grow()
780            .py_1()
781            .track_scroll(scroll_handle.clone())
782            .into_any_element(),
783            ElementContainer::List(state) => list(state.clone())
784                .with_sizing_behavior(sizing_behavior)
785                .flex_grow()
786                .py_2()
787                .into_any_element(),
788        }
789    }
790
791    #[cfg(any(test, feature = "test-support"))]
792    pub fn logical_scroll_top_index(&self) -> usize {
793        match &self.element_container {
794            ElementContainer::List(state) => state.logical_scroll_top().item_ix,
795            ElementContainer::UniformList(scroll_handle) => {
796                scroll_handle.logical_scroll_top_index()
797            }
798        }
799    }
800
801    fn hide_scrollbar(&mut self, cx: &mut Context<Self>) {
802        const SCROLLBAR_SHOW_INTERVAL: Duration = Duration::from_secs(1);
803        self.hide_scrollbar_task = Some(cx.spawn(async move |panel, cx| {
804            cx.background_executor()
805                .timer(SCROLLBAR_SHOW_INTERVAL)
806                .await;
807            panel
808                .update(cx, |panel, cx| {
809                    panel.scrollbar_visibility = false;
810                    cx.notify();
811                })
812                .log_err();
813        }))
814    }
815
816    fn render_scrollbar(&self, cx: &mut Context<Self>) -> Option<Stateful<Div>> {
817        if !self.show_scrollbar
818            || !(self.scrollbar_visibility || self.scrollbar_state.is_dragging())
819        {
820            return None;
821        }
822        Some(
823            div()
824                .occlude()
825                .id("picker-scroll")
826                .h_full()
827                .absolute()
828                .right_1()
829                .top_1()
830                .bottom_0()
831                .w(px(12.))
832                .cursor_default()
833                .on_mouse_move(cx.listener(|_, _, _window, cx| {
834                    cx.notify();
835                    cx.stop_propagation()
836                }))
837                .on_hover(|_, _window, cx| {
838                    cx.stop_propagation();
839                })
840                .on_any_mouse_down(|_, _window, cx| {
841                    cx.stop_propagation();
842                })
843                .on_mouse_up(
844                    MouseButton::Left,
845                    cx.listener(|picker, _, window, cx| {
846                        if !picker.scrollbar_state.is_dragging()
847                            && !picker.focus_handle.contains_focused(window, cx)
848                        {
849                            picker.hide_scrollbar(cx);
850                            cx.notify();
851                        }
852                        cx.stop_propagation();
853                    }),
854                )
855                .on_scroll_wheel(cx.listener(|_, _, _window, cx| {
856                    cx.notify();
857                }))
858                .children(Scrollbar::vertical(self.scrollbar_state.clone())),
859        )
860    }
861}
862
863impl<D: PickerDelegate> EventEmitter<DismissEvent> for Picker<D> {}
864impl<D: PickerDelegate> ModalView for Picker<D> {}
865
866impl<D: PickerDelegate> Render for Picker<D> {
867    fn render(&mut self, window: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
868        let editor_position = self.delegate.editor_position();
869        v_flex()
870            .key_context("Picker")
871            .size_full()
872            .when_some(self.width, |el, width| el.w(width))
873            .overflow_hidden()
874            // This is a bit of a hack to remove the modal styling when we're rendering the `Picker`
875            // as a part of a modal rather than the entire modal.
876            //
877            // We should revisit how the `Picker` is styled to make it more composable.
878            .when(self.is_modal, |this| this.elevation_3(cx))
879            .on_action(cx.listener(Self::select_next))
880            .on_action(cx.listener(Self::select_previous))
881            .on_action(cx.listener(Self::editor_move_down))
882            .on_action(cx.listener(Self::editor_move_up))
883            .on_action(cx.listener(Self::select_first))
884            .on_action(cx.listener(Self::select_last))
885            .on_action(cx.listener(Self::cancel))
886            .on_action(cx.listener(Self::confirm))
887            .on_action(cx.listener(Self::secondary_confirm))
888            .on_action(cx.listener(Self::confirm_completion))
889            .on_action(cx.listener(Self::confirm_input))
890            .children(match &self.head {
891                Head::Editor(editor) => {
892                    if editor_position == PickerEditorPosition::Start {
893                        Some(self.delegate.render_editor(&editor.clone(), window, cx))
894                    } else {
895                        None
896                    }
897                }
898                Head::Empty(empty_head) => Some(div().child(empty_head.clone())),
899            })
900            .when(self.delegate.match_count() > 0, |el| {
901                el.child(
902                    v_flex()
903                        .id("element-container")
904                        .relative()
905                        .flex_grow()
906                        .when_some(self.max_height, |div, max_h| div.max_h(max_h))
907                        .overflow_hidden()
908                        .children(self.delegate.render_header(window, cx))
909                        .child(self.render_element_container(cx))
910                        .on_hover(cx.listener(|this, hovered, window, cx| {
911                            if *hovered {
912                                this.scrollbar_visibility = true;
913                                this.hide_scrollbar_task.take();
914                                cx.notify();
915                            } else if !this.focus_handle.contains_focused(window, cx) {
916                                this.hide_scrollbar(cx);
917                            }
918                        }))
919                        .when_some(self.render_scrollbar(cx), |div, scrollbar| {
920                            div.child(scrollbar)
921                        }),
922                )
923            })
924            .when(self.delegate.match_count() == 0, |el| {
925                el.when_some(self.delegate.no_matches_text(window, cx), |el, text| {
926                    el.child(
927                        v_flex().flex_grow().py_2().child(
928                            ListItem::new("empty_state")
929                                .inset(true)
930                                .spacing(ListItemSpacing::Sparse)
931                                .disabled(true)
932                                .child(Label::new(text).color(Color::Muted)),
933                        ),
934                    )
935                })
936            })
937            .children(self.delegate.render_footer(window, cx))
938            .children(match &self.head {
939                Head::Editor(editor) => {
940                    if editor_position == PickerEditorPosition::End {
941                        Some(self.delegate.render_editor(&editor.clone(), window, cx))
942                    } else {
943                        None
944                    }
945                }
946                Head::Empty(empty_head) => Some(div().child(empty_head.clone())),
947            })
948    }
949}