pane.rs

  1use super::{ItemHandle, SplitDirection};
  2use crate::{Item, Settings, WeakItemHandle, Workspace};
  3use collections::{HashMap, VecDeque};
  4use gpui::{
  5    action,
  6    elements::*,
  7    geometry::{rect::RectF, vector::vec2f},
  8    keymap::Binding,
  9    platform::{CursorStyle, NavigationDirection},
 10    AnyViewHandle, AppContext, Entity, MutableAppContext, Quad, RenderContext, Task, View,
 11    ViewContext, ViewHandle, WeakViewHandle,
 12};
 13use project::{ProjectEntryId, ProjectPath};
 14use std::{
 15    any::{Any, TypeId},
 16    cell::RefCell,
 17    cmp, mem,
 18    rc::Rc,
 19};
 20use util::ResultExt;
 21
 22action!(Split, SplitDirection);
 23action!(ActivateItem, usize);
 24action!(ActivatePrevItem);
 25action!(ActivateNextItem);
 26action!(CloseActiveItem);
 27action!(CloseInactiveItems);
 28action!(CloseItem, usize);
 29action!(GoBack, Option<WeakViewHandle<Pane>>);
 30action!(GoForward, Option<WeakViewHandle<Pane>>);
 31
 32const MAX_NAVIGATION_HISTORY_LEN: usize = 1024;
 33
 34pub fn init(cx: &mut MutableAppContext) {
 35    cx.add_action(|pane: &mut Pane, action: &ActivateItem, cx| {
 36        pane.activate_item(action.0, cx);
 37    });
 38    cx.add_action(|pane: &mut Pane, _: &ActivatePrevItem, cx| {
 39        pane.activate_prev_item(cx);
 40    });
 41    cx.add_action(|pane: &mut Pane, _: &ActivateNextItem, cx| {
 42        pane.activate_next_item(cx);
 43    });
 44    cx.add_action(|pane: &mut Pane, _: &CloseActiveItem, cx| {
 45        pane.close_active_item(cx);
 46    });
 47    cx.add_action(|pane: &mut Pane, _: &CloseInactiveItems, cx| {
 48        pane.close_inactive_items(cx);
 49    });
 50    cx.add_action(|pane: &mut Pane, action: &CloseItem, cx| {
 51        pane.close_item(action.0, cx);
 52    });
 53    cx.add_action(|pane: &mut Pane, action: &Split, cx| {
 54        pane.split(action.0, cx);
 55    });
 56    cx.add_action(|workspace: &mut Workspace, action: &GoBack, cx| {
 57        Pane::go_back(
 58            workspace,
 59            action
 60                .0
 61                .as_ref()
 62                .and_then(|weak_handle| weak_handle.upgrade(cx)),
 63            cx,
 64        )
 65        .detach();
 66    });
 67    cx.add_action(|workspace: &mut Workspace, action: &GoForward, cx| {
 68        Pane::go_forward(
 69            workspace,
 70            action
 71                .0
 72                .as_ref()
 73                .and_then(|weak_handle| weak_handle.upgrade(cx)),
 74            cx,
 75        )
 76        .detach();
 77    });
 78
 79    cx.add_bindings(vec![
 80        Binding::new("shift-cmd-{", ActivatePrevItem, Some("Pane")),
 81        Binding::new("shift-cmd-}", ActivateNextItem, Some("Pane")),
 82        Binding::new("cmd-w", CloseActiveItem, Some("Pane")),
 83        Binding::new("alt-cmd-w", CloseInactiveItems, Some("Pane")),
 84        Binding::new("cmd-k up", Split(SplitDirection::Up), Some("Pane")),
 85        Binding::new("cmd-k down", Split(SplitDirection::Down), Some("Pane")),
 86        Binding::new("cmd-k left", Split(SplitDirection::Left), Some("Pane")),
 87        Binding::new("cmd-k right", Split(SplitDirection::Right), Some("Pane")),
 88        Binding::new("ctrl--", GoBack(None), Some("Pane")),
 89        Binding::new("shift-ctrl-_", GoForward(None), Some("Pane")),
 90    ]);
 91}
 92
 93pub enum Event {
 94    Activate,
 95    Remove,
 96    Split(SplitDirection),
 97}
 98
 99pub struct Pane {
100    items: Vec<Box<dyn ItemHandle>>,
101    active_item_index: usize,
102    nav_history: Rc<RefCell<NavHistory>>,
103    toolbars: HashMap<TypeId, Box<dyn ToolbarHandle>>,
104    active_toolbar_type: Option<TypeId>,
105    active_toolbar_visible: bool,
106}
107
108pub trait Toolbar: View {
109    fn active_item_changed(
110        &mut self,
111        item: Option<Box<dyn ItemHandle>>,
112        cx: &mut ViewContext<Self>,
113    ) -> bool;
114    fn on_dismiss(&mut self, cx: &mut ViewContext<Self>);
115}
116
117trait ToolbarHandle {
118    fn active_item_changed(
119        &self,
120        item: Option<Box<dyn ItemHandle>>,
121        cx: &mut MutableAppContext,
122    ) -> bool;
123    fn on_dismiss(&self, cx: &mut MutableAppContext);
124    fn to_any(&self) -> AnyViewHandle;
125}
126
127pub struct ItemNavHistory {
128    history: Rc<RefCell<NavHistory>>,
129    item: Rc<dyn WeakItemHandle>,
130}
131
132#[derive(Default)]
133pub struct NavHistory {
134    mode: NavigationMode,
135    backward_stack: VecDeque<NavigationEntry>,
136    forward_stack: VecDeque<NavigationEntry>,
137    paths_by_item: HashMap<usize, ProjectPath>,
138}
139
140#[derive(Copy, Clone)]
141enum NavigationMode {
142    Normal,
143    GoingBack,
144    GoingForward,
145    Disabled,
146}
147
148impl Default for NavigationMode {
149    fn default() -> Self {
150        Self::Normal
151    }
152}
153
154pub struct NavigationEntry {
155    pub item: Rc<dyn WeakItemHandle>,
156    pub data: Option<Box<dyn Any>>,
157}
158
159impl Pane {
160    pub fn new() -> Self {
161        Self {
162            items: Vec::new(),
163            active_item_index: 0,
164            nav_history: Default::default(),
165            toolbars: Default::default(),
166            active_toolbar_type: Default::default(),
167            active_toolbar_visible: false,
168        }
169    }
170
171    pub fn nav_history(&self) -> &Rc<RefCell<NavHistory>> {
172        &self.nav_history
173    }
174
175    pub fn activate(&self, cx: &mut ViewContext<Self>) {
176        cx.emit(Event::Activate);
177    }
178
179    pub fn go_back(
180        workspace: &mut Workspace,
181        pane: Option<ViewHandle<Pane>>,
182        cx: &mut ViewContext<Workspace>,
183    ) -> Task<()> {
184        Self::navigate_history(
185            workspace,
186            pane.unwrap_or_else(|| workspace.active_pane().clone()),
187            NavigationMode::GoingBack,
188            cx,
189        )
190    }
191
192    pub fn go_forward(
193        workspace: &mut Workspace,
194        pane: Option<ViewHandle<Pane>>,
195        cx: &mut ViewContext<Workspace>,
196    ) -> Task<()> {
197        Self::navigate_history(
198            workspace,
199            pane.unwrap_or_else(|| workspace.active_pane().clone()),
200            NavigationMode::GoingForward,
201            cx,
202        )
203    }
204
205    fn navigate_history(
206        workspace: &mut Workspace,
207        pane: ViewHandle<Pane>,
208        mode: NavigationMode,
209        cx: &mut ViewContext<Workspace>,
210    ) -> Task<()> {
211        workspace.activate_pane(pane.clone(), cx);
212
213        let to_load = pane.update(cx, |pane, cx| {
214            // Retrieve the weak item handle from the history.
215            let entry = pane.nav_history.borrow_mut().pop(mode)?;
216
217            // If the item is still present in this pane, then activate it.
218            if let Some(index) = entry
219                .item
220                .upgrade(cx)
221                .and_then(|v| pane.index_for_item(v.as_ref()))
222            {
223                if let Some(item) = pane.active_item() {
224                    pane.nav_history.borrow_mut().set_mode(mode);
225                    item.deactivated(cx);
226                    pane.nav_history
227                        .borrow_mut()
228                        .set_mode(NavigationMode::Normal);
229                }
230
231                pane.active_item_index = index;
232                pane.focus_active_item(cx);
233                if let Some(data) = entry.data {
234                    pane.active_item()?.navigate(data, cx);
235                }
236                cx.notify();
237                None
238            }
239            // If the item is no longer present in this pane, then retrieve its
240            // project path in order to reopen it.
241            else {
242                pane.nav_history
243                    .borrow_mut()
244                    .paths_by_item
245                    .get(&entry.item.id())
246                    .cloned()
247                    .map(|project_path| (project_path, entry))
248            }
249        });
250
251        if let Some((project_path, entry)) = to_load {
252            // If the item was no longer present, then load it again from its previous path.
253            let pane = pane.downgrade();
254            let task = workspace.load_path(project_path, cx);
255            cx.spawn(|workspace, mut cx| async move {
256                let task = task.await;
257                if let Some(pane) = pane.upgrade(&cx) {
258                    if let Some((project_entry_id, build_item)) = task.log_err() {
259                        pane.update(&mut cx, |pane, _| {
260                            pane.nav_history.borrow_mut().set_mode(mode);
261                        });
262                        let item = workspace.update(&mut cx, |workspace, cx| {
263                            Self::open_item(
264                                workspace,
265                                pane.clone(),
266                                project_entry_id,
267                                cx,
268                                build_item,
269                            )
270                        });
271                        pane.update(&mut cx, |pane, cx| {
272                            pane.nav_history
273                                .borrow_mut()
274                                .set_mode(NavigationMode::Normal);
275                            if let Some(data) = entry.data {
276                                item.navigate(data, cx);
277                            }
278                        });
279                    } else {
280                        workspace
281                            .update(&mut cx, |workspace, cx| {
282                                Self::navigate_history(workspace, pane, mode, cx)
283                            })
284                            .await;
285                    }
286                }
287            })
288        } else {
289            Task::ready(())
290        }
291    }
292
293    pub(crate) fn open_item(
294        workspace: &mut Workspace,
295        pane: ViewHandle<Pane>,
296        project_entry_id: ProjectEntryId,
297        cx: &mut ViewContext<Workspace>,
298        build_item: impl FnOnce(&mut MutableAppContext) -> Box<dyn ItemHandle>,
299    ) -> Box<dyn ItemHandle> {
300        let existing_item = pane.update(cx, |pane, cx| {
301            for (ix, item) in pane.items.iter().enumerate() {
302                if item.project_entry_id(cx) == Some(project_entry_id) {
303                    let item = item.boxed_clone();
304                    pane.activate_item(ix, cx);
305                    return Some(item);
306                }
307            }
308            None
309        });
310        if let Some(existing_item) = existing_item {
311            existing_item
312        } else {
313            let item = build_item(cx);
314            Self::add_item(workspace, pane, item.boxed_clone(), cx);
315            item
316        }
317    }
318
319    pub(crate) fn add_item(
320        workspace: &mut Workspace,
321        pane: ViewHandle<Pane>,
322        item: Box<dyn ItemHandle>,
323        cx: &mut ViewContext<Workspace>,
324    ) {
325        // Prevent adding the same item to the pane more than once.
326        if let Some(item_ix) = pane.read(cx).items.iter().position(|i| i.id() == item.id()) {
327            pane.update(cx, |pane, cx| pane.activate_item(item_ix, cx));
328            return;
329        }
330
331        item.set_nav_history(pane.read(cx).nav_history.clone(), cx);
332        item.added_to_pane(workspace, pane.clone(), cx);
333        pane.update(cx, |pane, cx| {
334            let item_idx = cmp::min(pane.active_item_index + 1, pane.items.len());
335            pane.items.insert(item_idx, item);
336            pane.activate_item(item_idx, cx);
337            cx.notify();
338        });
339    }
340
341    pub fn items(&self) -> impl Iterator<Item = &Box<dyn ItemHandle>> {
342        self.items.iter()
343    }
344
345    pub fn items_of_type<'a, T: View>(&'a self) -> impl 'a + Iterator<Item = ViewHandle<T>> {
346        self.items
347            .iter()
348            .filter_map(|item| item.to_any().downcast())
349    }
350
351    pub fn active_item(&self) -> Option<Box<dyn ItemHandle>> {
352        self.items.get(self.active_item_index).cloned()
353    }
354
355    pub fn project_entry_id_for_item(
356        &self,
357        item: &dyn ItemHandle,
358        cx: &AppContext,
359    ) -> Option<ProjectEntryId> {
360        self.items.iter().find_map(|existing| {
361            if existing.id() == item.id() {
362                existing.project_entry_id(cx)
363            } else {
364                None
365            }
366        })
367    }
368
369    pub fn item_for_entry(
370        &self,
371        entry_id: ProjectEntryId,
372        cx: &AppContext,
373    ) -> Option<Box<dyn ItemHandle>> {
374        self.items.iter().find_map(|item| {
375            if item.project_entry_id(cx) == Some(entry_id) {
376                Some(item.boxed_clone())
377            } else {
378                None
379            }
380        })
381    }
382
383    pub fn index_for_item(&self, item: &dyn ItemHandle) -> Option<usize> {
384        self.items.iter().position(|i| i.id() == item.id())
385    }
386
387    pub fn activate_item(&mut self, index: usize, cx: &mut ViewContext<Self>) {
388        if index < self.items.len() {
389            let prev_active_item_ix = mem::replace(&mut self.active_item_index, index);
390            if prev_active_item_ix != self.active_item_index
391                && prev_active_item_ix < self.items.len()
392            {
393                self.items[prev_active_item_ix].deactivated(cx);
394            }
395            self.update_active_toolbar(cx);
396            self.focus_active_item(cx);
397            self.activate(cx);
398            cx.notify();
399        }
400    }
401
402    pub fn activate_prev_item(&mut self, cx: &mut ViewContext<Self>) {
403        let mut index = self.active_item_index;
404        if index > 0 {
405            index -= 1;
406        } else if self.items.len() > 0 {
407            index = self.items.len() - 1;
408        }
409        self.activate_item(index, cx);
410    }
411
412    pub fn activate_next_item(&mut self, cx: &mut ViewContext<Self>) {
413        let mut index = self.active_item_index;
414        if index + 1 < self.items.len() {
415            index += 1;
416        } else {
417            index = 0;
418        }
419        self.activate_item(index, cx);
420    }
421
422    pub fn close_active_item(&mut self, cx: &mut ViewContext<Self>) {
423        if !self.items.is_empty() {
424            self.close_item(self.items[self.active_item_index].id(), cx)
425        }
426    }
427
428    pub fn close_inactive_items(&mut self, cx: &mut ViewContext<Self>) {
429        if !self.items.is_empty() {
430            let active_item_id = self.items[self.active_item_index].id();
431            self.close_items(cx, |id| id != active_item_id);
432        }
433    }
434
435    pub fn close_item(&mut self, view_id_to_close: usize, cx: &mut ViewContext<Self>) {
436        self.close_items(cx, |view_id| view_id == view_id_to_close);
437    }
438
439    pub fn close_items(
440        &mut self,
441        cx: &mut ViewContext<Self>,
442        should_close: impl Fn(usize) -> bool,
443    ) {
444        let mut item_ix = 0;
445        let mut new_active_item_index = self.active_item_index;
446        self.items.retain(|item| {
447            if should_close(item.id()) {
448                if item_ix == self.active_item_index {
449                    item.deactivated(cx);
450                }
451
452                if item_ix < self.active_item_index {
453                    new_active_item_index -= 1;
454                }
455
456                let mut nav_history = self.nav_history.borrow_mut();
457                if let Some(path) = item.project_path(cx) {
458                    nav_history.paths_by_item.insert(item.id(), path);
459                } else {
460                    nav_history.paths_by_item.remove(&item.id());
461                }
462
463                item_ix += 1;
464                false
465            } else {
466                item_ix += 1;
467                true
468            }
469        });
470
471        if self.items.is_empty() {
472            cx.emit(Event::Remove);
473        } else {
474            self.active_item_index = cmp::min(new_active_item_index, self.items.len() - 1);
475            self.focus_active_item(cx);
476            self.activate(cx);
477        }
478        self.update_active_toolbar(cx);
479
480        cx.notify();
481    }
482
483    fn focus_active_item(&mut self, cx: &mut ViewContext<Self>) {
484        if let Some(active_item) = self.active_item() {
485            cx.focus(active_item);
486        }
487    }
488
489    pub fn split(&mut self, direction: SplitDirection, cx: &mut ViewContext<Self>) {
490        cx.emit(Event::Split(direction));
491    }
492
493    pub fn show_toolbar<F, V>(&mut self, cx: &mut ViewContext<Self>, build_toolbar: F)
494    where
495        F: FnOnce(&mut ViewContext<V>) -> V,
496        V: Toolbar,
497    {
498        let type_id = TypeId::of::<V>();
499        if self.active_toolbar_type != Some(type_id) {
500            self.dismiss_toolbar(cx);
501
502            let active_item = self.active_item();
503            self.toolbars
504                .entry(type_id)
505                .or_insert_with(|| Box::new(cx.add_view(build_toolbar)));
506
507            self.active_toolbar_type = Some(type_id);
508            self.active_toolbar_visible =
509                self.toolbars[&type_id].active_item_changed(active_item, cx);
510            cx.notify();
511        }
512    }
513
514    pub fn dismiss_toolbar(&mut self, cx: &mut ViewContext<Self>) {
515        if let Some(active_toolbar_type) = self.active_toolbar_type.take() {
516            self.toolbars
517                .get_mut(&active_toolbar_type)
518                .unwrap()
519                .on_dismiss(cx);
520            self.active_toolbar_visible = false;
521            self.focus_active_item(cx);
522            cx.notify();
523        }
524    }
525
526    pub fn toolbar<T: Toolbar>(&self) -> Option<ViewHandle<T>> {
527        self.toolbars
528            .get(&TypeId::of::<T>())
529            .and_then(|toolbar| toolbar.to_any().downcast())
530    }
531
532    pub fn active_toolbar(&self) -> Option<AnyViewHandle> {
533        let type_id = self.active_toolbar_type?;
534        let toolbar = self.toolbars.get(&type_id)?;
535        if self.active_toolbar_visible {
536            Some(toolbar.to_any())
537        } else {
538            None
539        }
540    }
541
542    fn update_active_toolbar(&mut self, cx: &mut ViewContext<Self>) {
543        let active_item = self.items.get(self.active_item_index);
544        for (toolbar_type_id, toolbar) in &self.toolbars {
545            let visible = toolbar.active_item_changed(active_item.cloned(), cx);
546            if Some(*toolbar_type_id) == self.active_toolbar_type {
547                self.active_toolbar_visible = visible;
548            }
549        }
550    }
551
552    fn render_tabs(&self, cx: &mut RenderContext<Self>) -> ElementBox {
553        let theme = cx.global::<Settings>().theme.clone();
554
555        enum Tabs {}
556        let tabs = MouseEventHandler::new::<Tabs, _, _>(0, cx, |mouse_state, cx| {
557            let mut row = Flex::row();
558            for (ix, item) in self.items.iter().enumerate() {
559                let is_active = ix == self.active_item_index;
560
561                row.add_child({
562                    let tab_style = if is_active {
563                        theme.workspace.active_tab.clone()
564                    } else {
565                        theme.workspace.tab.clone()
566                    };
567                    let title = item.tab_content(&tab_style, cx);
568
569                    let mut style = if is_active {
570                        theme.workspace.active_tab.clone()
571                    } else {
572                        theme.workspace.tab.clone()
573                    };
574                    if ix == 0 {
575                        style.container.border.left = false;
576                    }
577
578                    EventHandler::new(
579                        Container::new(
580                            Flex::row()
581                                .with_child(
582                                    Align::new({
583                                        let diameter = 7.0;
584                                        let icon_color = if item.has_conflict(cx) {
585                                            Some(style.icon_conflict)
586                                        } else if item.is_dirty(cx) {
587                                            Some(style.icon_dirty)
588                                        } else {
589                                            None
590                                        };
591
592                                        ConstrainedBox::new(
593                                            Canvas::new(move |bounds, _, cx| {
594                                                if let Some(color) = icon_color {
595                                                    let square = RectF::new(
596                                                        bounds.origin(),
597                                                        vec2f(diameter, diameter),
598                                                    );
599                                                    cx.scene.push_quad(Quad {
600                                                        bounds: square,
601                                                        background: Some(color),
602                                                        border: Default::default(),
603                                                        corner_radius: diameter / 2.,
604                                                    });
605                                                }
606                                            })
607                                            .boxed(),
608                                        )
609                                        .with_width(diameter)
610                                        .with_height(diameter)
611                                        .boxed()
612                                    })
613                                    .boxed(),
614                                )
615                                .with_child(
616                                    Container::new(Align::new(title).boxed())
617                                        .with_style(ContainerStyle {
618                                            margin: Margin {
619                                                left: style.spacing,
620                                                right: style.spacing,
621                                                ..Default::default()
622                                            },
623                                            ..Default::default()
624                                        })
625                                        .boxed(),
626                                )
627                                .with_child(
628                                    Align::new(
629                                        ConstrainedBox::new(if mouse_state.hovered {
630                                            let item_id = item.id();
631                                            enum TabCloseButton {}
632                                            let icon = Svg::new("icons/x.svg");
633                                            MouseEventHandler::new::<TabCloseButton, _, _>(
634                                                item_id,
635                                                cx,
636                                                |mouse_state, _| {
637                                                    if mouse_state.hovered {
638                                                        icon.with_color(style.icon_close_active)
639                                                            .boxed()
640                                                    } else {
641                                                        icon.with_color(style.icon_close).boxed()
642                                                    }
643                                                },
644                                            )
645                                            .with_padding(Padding::uniform(4.))
646                                            .with_cursor_style(CursorStyle::PointingHand)
647                                            .on_click(move |cx| {
648                                                cx.dispatch_action(CloseItem(item_id))
649                                            })
650                                            .named("close-tab-icon")
651                                        } else {
652                                            Empty::new().boxed()
653                                        })
654                                        .with_width(style.icon_width)
655                                        .boxed(),
656                                    )
657                                    .boxed(),
658                                )
659                                .boxed(),
660                        )
661                        .with_style(style.container)
662                        .boxed(),
663                    )
664                    .on_mouse_down(move |cx| {
665                        cx.dispatch_action(ActivateItem(ix));
666                        true
667                    })
668                    .boxed()
669                })
670            }
671
672            row.add_child(
673                Empty::new()
674                    .contained()
675                    .with_border(theme.workspace.tab.container.border)
676                    .flexible(0., true)
677                    .named("filler"),
678            );
679
680            row.boxed()
681        });
682
683        ConstrainedBox::new(tabs.boxed())
684            .with_height(theme.workspace.tab.height)
685            .named("tabs")
686    }
687}
688
689impl Entity for Pane {
690    type Event = Event;
691}
692
693impl View for Pane {
694    fn ui_name() -> &'static str {
695        "Pane"
696    }
697
698    fn render(&mut self, cx: &mut RenderContext<Self>) -> ElementBox {
699        let this = cx.handle();
700
701        EventHandler::new(if let Some(active_item) = self.active_item() {
702            Flex::column()
703                .with_child(self.render_tabs(cx))
704                .with_children(
705                    self.active_toolbar()
706                        .as_ref()
707                        .map(|view| ChildView::new(view).boxed()),
708                )
709                .with_child(ChildView::new(active_item).flexible(1., true).boxed())
710                .boxed()
711        } else {
712            Empty::new().boxed()
713        })
714        .on_navigate_mouse_down(move |direction, cx| {
715            let this = this.clone();
716            match direction {
717                NavigationDirection::Back => cx.dispatch_action(GoBack(Some(this))),
718                NavigationDirection::Forward => cx.dispatch_action(GoForward(Some(this))),
719            }
720
721            true
722        })
723        .named("pane")
724    }
725
726    fn on_focus(&mut self, cx: &mut ViewContext<Self>) {
727        self.focus_active_item(cx);
728    }
729}
730
731impl<T: Toolbar> ToolbarHandle for ViewHandle<T> {
732    fn active_item_changed(
733        &self,
734        item: Option<Box<dyn ItemHandle>>,
735        cx: &mut MutableAppContext,
736    ) -> bool {
737        self.update(cx, |this, cx| this.active_item_changed(item, cx))
738    }
739
740    fn on_dismiss(&self, cx: &mut MutableAppContext) {
741        self.update(cx, |this, cx| this.on_dismiss(cx));
742    }
743
744    fn to_any(&self) -> AnyViewHandle {
745        self.into()
746    }
747}
748
749impl ItemNavHistory {
750    pub fn new<T: Item>(history: Rc<RefCell<NavHistory>>, item: &ViewHandle<T>) -> Self {
751        Self {
752            history,
753            item: Rc::new(item.downgrade()),
754        }
755    }
756
757    pub fn history(&self) -> Rc<RefCell<NavHistory>> {
758        self.history.clone()
759    }
760
761    pub fn push<D: 'static + Any>(&self, data: Option<D>) {
762        self.history.borrow_mut().push(data, self.item.clone());
763    }
764}
765
766impl NavHistory {
767    pub fn disable(&mut self) {
768        self.mode = NavigationMode::Disabled;
769    }
770
771    pub fn enable(&mut self) {
772        self.mode = NavigationMode::Normal;
773    }
774
775    pub fn pop_backward(&mut self) -> Option<NavigationEntry> {
776        self.backward_stack.pop_back()
777    }
778
779    pub fn pop_forward(&mut self) -> Option<NavigationEntry> {
780        self.forward_stack.pop_back()
781    }
782
783    fn pop(&mut self, mode: NavigationMode) -> Option<NavigationEntry> {
784        match mode {
785            NavigationMode::Normal | NavigationMode::Disabled => None,
786            NavigationMode::GoingBack => self.pop_backward(),
787            NavigationMode::GoingForward => self.pop_forward(),
788        }
789    }
790
791    fn set_mode(&mut self, mode: NavigationMode) {
792        self.mode = mode;
793    }
794
795    pub fn push<D: 'static + Any>(&mut self, data: Option<D>, item: Rc<dyn WeakItemHandle>) {
796        match self.mode {
797            NavigationMode::Disabled => {}
798            NavigationMode::Normal => {
799                if self.backward_stack.len() >= MAX_NAVIGATION_HISTORY_LEN {
800                    self.backward_stack.pop_front();
801                }
802                self.backward_stack.push_back(NavigationEntry {
803                    item,
804                    data: data.map(|data| Box::new(data) as Box<dyn Any>),
805                });
806                self.forward_stack.clear();
807            }
808            NavigationMode::GoingBack => {
809                if self.forward_stack.len() >= MAX_NAVIGATION_HISTORY_LEN {
810                    self.forward_stack.pop_front();
811                }
812                self.forward_stack.push_back(NavigationEntry {
813                    item,
814                    data: data.map(|data| Box::new(data) as Box<dyn Any>),
815                });
816            }
817            NavigationMode::GoingForward => {
818                if self.backward_stack.len() >= MAX_NAVIGATION_HISTORY_LEN {
819                    self.backward_stack.pop_front();
820                }
821                self.backward_stack.push_back(NavigationEntry {
822                    item,
823                    data: data.map(|data| Box::new(data) as Box<dyn Any>),
824                });
825            }
826        }
827    }
828}