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gpui_core/elements/
text.rs

1use crate::{
2    ActiveTooltip, AnyView, App, Bounds, DispatchPhase, Element, ElementId, GlobalElementId,
3    HighlightStyle, Hitbox, HitboxBehavior, InspectorElementId, IntoElement, LayoutId,
4    MouseDownEvent, MouseMoveEvent, MouseUpEvent, Pixels, Point, SharedString, Size, TextOverflow,
5    TextRun, TextStyle, TooltipId, WhiteSpace, Window, WrappedLine, WrappedLineLayout,
6    register_tooltip_mouse_handlers, set_tooltip_on_window,
7};
8use anyhow::Context as _;
9use smallvec::SmallVec;
10use std::{
11    cell::{Cell, RefCell},
12    mem,
13    ops::Range,
14    rc::Rc,
15    sync::Arc,
16};
17use util::ResultExt;
18
19impl Element for &'static str {
20    type RequestLayoutState = TextLayout;
21    type PrepaintState = ();
22
23    fn id(&self) -> Option<ElementId> {
24        None
25    }
26
27    fn source_location(&self) -> Option<&'static core::panic::Location<'static>> {
28        None
29    }
30
31    fn request_layout(
32        &mut self,
33        _id: Option<&GlobalElementId>,
34        _inspector_id: Option<&InspectorElementId>,
35        window: &mut Window,
36        cx: &mut App,
37    ) -> (LayoutId, Self::RequestLayoutState) {
38        let mut state = TextLayout::default();
39        let layout_id = state.layout(SharedString::from(*self), None, window, cx);
40        (layout_id, state)
41    }
42
43    fn prepaint(
44        &mut self,
45        _id: Option<&GlobalElementId>,
46        _inspector_id: Option<&InspectorElementId>,
47        bounds: Bounds<Pixels>,
48        text_layout: &mut Self::RequestLayoutState,
49        _window: &mut Window,
50        _cx: &mut App,
51    ) {
52        text_layout.prepaint(bounds, self)
53    }
54
55    fn paint(
56        &mut self,
57        _id: Option<&GlobalElementId>,
58        _inspector_id: Option<&InspectorElementId>,
59        _bounds: Bounds<Pixels>,
60        text_layout: &mut TextLayout,
61        _: &mut (),
62        window: &mut Window,
63        cx: &mut App,
64    ) {
65        text_layout.paint(self, window, cx)
66    }
67}
68
69impl IntoElement for &'static str {
70    type Element = Self;
71
72    fn into_element(self) -> Self::Element {
73        self
74    }
75}
76
77impl IntoElement for String {
78    type Element = SharedString;
79
80    fn into_element(self) -> Self::Element {
81        self.into()
82    }
83}
84
85impl Element for SharedString {
86    type RequestLayoutState = TextLayout;
87    type PrepaintState = ();
88
89    fn id(&self) -> Option<ElementId> {
90        None
91    }
92
93    fn source_location(&self) -> Option<&'static core::panic::Location<'static>> {
94        None
95    }
96
97    fn request_layout(
98        &mut self,
99        _id: Option<&GlobalElementId>,
100        _inspector_id: Option<&InspectorElementId>,
101        window: &mut Window,
102        cx: &mut App,
103    ) -> (LayoutId, Self::RequestLayoutState) {
104        let mut state = TextLayout::default();
105        let layout_id = state.layout(self.clone(), None, window, cx);
106        (layout_id, state)
107    }
108
109    fn prepaint(
110        &mut self,
111        _id: Option<&GlobalElementId>,
112        _inspector_id: Option<&InspectorElementId>,
113        bounds: Bounds<Pixels>,
114        text_layout: &mut Self::RequestLayoutState,
115        _window: &mut Window,
116        _cx: &mut App,
117    ) {
118        text_layout.prepaint(bounds, self.as_ref())
119    }
120
121    fn paint(
122        &mut self,
123        _id: Option<&GlobalElementId>,
124        _inspector_id: Option<&InspectorElementId>,
125        _bounds: Bounds<Pixels>,
126        text_layout: &mut Self::RequestLayoutState,
127        _: &mut Self::PrepaintState,
128        window: &mut Window,
129        cx: &mut App,
130    ) {
131        text_layout.paint(self.as_ref(), window, cx)
132    }
133}
134
135impl IntoElement for SharedString {
136    type Element = Self;
137
138    fn into_element(self) -> Self::Element {
139        self
140    }
141}
142
143/// Renders text with runs of different styles.
144///
145/// Callers are responsible for setting the correct style for each run.
146/// For text with a uniform style, you can usually avoid calling this constructor
147/// and just pass text directly.
148pub struct StyledText {
149    text: SharedString,
150    runs: Option<Vec<TextRun>>,
151    delayed_highlights: Option<Vec<(Range<usize>, HighlightStyle)>>,
152    layout: TextLayout,
153}
154
155impl StyledText {
156    /// Construct a new styled text element from the given string.
157    pub fn new(text: impl Into<SharedString>) -> Self {
158        StyledText {
159            text: text.into(),
160            runs: None,
161            delayed_highlights: None,
162            layout: TextLayout::default(),
163        }
164    }
165
166    /// Get the layout for this element. This can be used to map indices to pixels and vice versa.
167    pub fn layout(&self) -> &TextLayout {
168        &self.layout
169    }
170
171    /// Set the styling attributes for the given text, as well as
172    /// as any ranges of text that have had their style customized.
173    pub fn with_default_highlights(
174        mut self,
175        default_style: &TextStyle,
176        highlights: impl IntoIterator<Item = (Range<usize>, HighlightStyle)>,
177    ) -> Self {
178        debug_assert!(
179            self.delayed_highlights.is_none(),
180            "Can't use `with_default_highlights` and `with_highlights`"
181        );
182        let runs = Self::compute_runs(&self.text, default_style, highlights);
183        self.runs = Some(runs);
184        self
185    }
186
187    /// Set the styling attributes for the given text, as well as
188    /// as any ranges of text that have had their style customized.
189    pub fn with_highlights(
190        mut self,
191        highlights: impl IntoIterator<Item = (Range<usize>, HighlightStyle)>,
192    ) -> Self {
193        debug_assert!(
194            self.runs.is_none(),
195            "Can't use `with_highlights` and `with_default_highlights`"
196        );
197        self.delayed_highlights = Some(highlights.into_iter().collect::<Vec<_>>());
198        self
199    }
200
201    fn compute_runs(
202        text: &str,
203        default_style: &TextStyle,
204        highlights: impl IntoIterator<Item = (Range<usize>, HighlightStyle)>,
205    ) -> Vec<TextRun> {
206        let mut runs = Vec::new();
207        let mut ix = 0;
208        for (range, highlight) in highlights {
209            if ix < range.start {
210                runs.push(default_style.clone().to_run(range.start - ix));
211            }
212            runs.push(
213                default_style
214                    .clone()
215                    .highlight(highlight)
216                    .to_run(range.len()),
217            );
218            ix = range.end;
219        }
220        if ix < text.len() {
221            runs.push(default_style.to_run(text.len() - ix));
222        }
223        runs
224    }
225
226    /// Set the text runs for this piece of text.
227    pub fn with_runs(mut self, runs: Vec<TextRun>) -> Self {
228        self.runs = Some(runs);
229        self
230    }
231}
232
233impl Element for StyledText {
234    type RequestLayoutState = ();
235    type PrepaintState = ();
236
237    fn id(&self) -> Option<ElementId> {
238        None
239    }
240
241    fn source_location(&self) -> Option<&'static core::panic::Location<'static>> {
242        None
243    }
244
245    fn request_layout(
246        &mut self,
247        _id: Option<&GlobalElementId>,
248        _inspector_id: Option<&InspectorElementId>,
249        window: &mut Window,
250        cx: &mut App,
251    ) -> (LayoutId, Self::RequestLayoutState) {
252        let runs = self.runs.take().or_else(|| {
253            self.delayed_highlights.take().map(|delayed_highlights| {
254                Self::compute_runs(&self.text, &window.text_style(), delayed_highlights)
255            })
256        });
257
258        let layout_id = self.layout.layout(self.text.clone(), runs, window, cx);
259        (layout_id, ())
260    }
261
262    fn prepaint(
263        &mut self,
264        _id: Option<&GlobalElementId>,
265        _inspector_id: Option<&InspectorElementId>,
266        bounds: Bounds<Pixels>,
267        _: &mut Self::RequestLayoutState,
268        _window: &mut Window,
269        _cx: &mut App,
270    ) {
271        self.layout.prepaint(bounds, &self.text)
272    }
273
274    fn paint(
275        &mut self,
276        _id: Option<&GlobalElementId>,
277        _inspector_id: Option<&InspectorElementId>,
278        _bounds: Bounds<Pixels>,
279        _: &mut Self::RequestLayoutState,
280        _: &mut Self::PrepaintState,
281        window: &mut Window,
282        cx: &mut App,
283    ) {
284        self.layout.paint(&self.text, window, cx)
285    }
286}
287
288impl IntoElement for StyledText {
289    type Element = Self;
290
291    fn into_element(self) -> Self::Element {
292        self
293    }
294}
295
296/// The Layout for TextElement. This can be used to map indices to pixels and vice versa.
297#[derive(Default, Clone)]
298pub struct TextLayout(Rc<RefCell<Option<TextLayoutInner>>>);
299
300struct TextLayoutInner {
301    len: usize,
302    lines: SmallVec<[WrappedLine; 1]>,
303    line_height: Pixels,
304    wrap_width: Option<Pixels>,
305    truncate_width: Option<Pixels>,
306    size: Option<Size<Pixels>>,
307    bounds: Option<Bounds<Pixels>>,
308}
309
310fn cached_size_for_constraints(
311    cached: &TextLayoutInner,
312    wrap_width: Option<Pixels>,
313    truncate_width: Option<Pixels>,
314) -> Option<Size<Pixels>> {
315    if (wrap_width.is_none() || wrap_width == cached.wrap_width)
316        && truncate_width.is_none()
317        && cached.truncate_width.is_none()
318    {
319        cached.size
320    } else {
321        None
322    }
323}
324
325fn all_shaped_line_widths_fit(
326    widths: impl IntoIterator<Item = Pixels>,
327    truncate_width: Pixels,
328) -> bool {
329    widths.into_iter().all(|width| width <= truncate_width)
330}
331
332impl TextLayout {
333    fn layout(
334        &self,
335        text: SharedString,
336        runs: Option<Vec<TextRun>>,
337        window: &mut Window,
338        _: &mut App,
339    ) -> LayoutId {
340        let text_style = window.text_style();
341        let font_size = text_style.font_size.to_pixels(window.rem_size());
342        let line_height = window.pixel_snap(
343            text_style
344                .line_height
345                .to_pixels(font_size.into(), window.rem_size()),
346        );
347
348        let mut runs = if let Some(runs) = runs {
349            runs
350        } else {
351            vec![text_style.to_run(text.len())]
352        };
353
354        window.request_measured_layout(Default::default(), {
355            let element_state = self.clone();
356
357            move |known_dimensions, available_space, window, cx| {
358                let wrap_width = if text_style.white_space == WhiteSpace::Normal {
359                    known_dimensions.width.or(match available_space.width {
360                        crate::AvailableSpace::Definite(x) => Some(x),
361                        _ => None,
362                    })
363                } else {
364                    None
365                };
366
367                let (truncate_width, truncation_suffix) =
368                    if let Some(text_overflow) = text_style.text_overflow.clone() {
369                        let width = known_dimensions.width.or(match available_space.width {
370                            crate::AvailableSpace::Definite(x) => match text_style.line_clamp {
371                                Some(max_lines) => Some(x * max_lines),
372                                None => Some(x),
373                            },
374                            _ => None,
375                        });
376
377                        match text_overflow {
378                            TextOverflow::Truncate(s) => (width, s),
379                        }
380                    } else {
381                        (None, "".into())
382                    };
383
384                if let Some(size) = element_state.0.borrow().as_ref().and_then(|cached| {
385                    cached_size_for_constraints(cached, wrap_width, truncate_width)
386                }) {
387                    return size;
388                }
389
390                let mut line_wrapper = cx.text_system().line_wrapper(text_style.font(), font_size);
391                let text = if let Some(truncate_width) = truncate_width {
392                    let unclipped_text_fits = wrap_width.is_none()
393                        && window
394                            .text_system()
395                            .shape_text(text.clone(), font_size, &runs, None, None)
396                            .log_err()
397                            .is_some_and(|lines| {
398                                all_shaped_line_widths_fit(
399                                    lines.iter().map(|line| line.size(line_height).width),
400                                    truncate_width,
401                                )
402                            });
403
404                    if unclipped_text_fits {
405                        text.clone()
406                    } else {
407                        line_wrapper.truncate_line(
408                            text.clone(),
409                            truncate_width,
410                            &truncation_suffix,
411                            &mut runs,
412                        )
413                    }
414                } else {
415                    text.clone()
416                };
417                let len = text.len();
418
419                let Some(lines) = window
420                    .text_system()
421                    .shape_text(
422                        text,
423                        font_size,
424                        &runs,
425                        wrap_width,            // Wrap if we know the width.
426                        text_style.line_clamp, // Limit the number of lines if line_clamp is set.
427                    )
428                    .log_err()
429                else {
430                    element_state.0.borrow_mut().replace(TextLayoutInner {
431                        lines: Default::default(),
432                        len: 0,
433                        line_height,
434                        wrap_width,
435                        truncate_width,
436                        size: Some(Size::default()),
437                        bounds: None,
438                    });
439                    return Size::default();
440                };
441
442                let mut size: Size<Pixels> = Size::default();
443                for line in &lines {
444                    let line_size = line.size(line_height);
445                    size.height += line_size.height;
446                    size.width = size.width.max(line_size.width).ceil();
447                }
448
449                element_state.0.borrow_mut().replace(TextLayoutInner {
450                    lines,
451                    len,
452                    line_height,
453                    wrap_width,
454                    truncate_width,
455                    size: Some(size),
456                    bounds: None,
457                });
458
459                size
460            }
461        })
462    }
463
464    fn prepaint(&self, bounds: Bounds<Pixels>, text: &str) {
465        let mut element_state = self.0.borrow_mut();
466        let element_state = element_state
467            .as_mut()
468            .with_context(|| format!("measurement has not been performed on {text}"))
469            .unwrap();
470        element_state.bounds = Some(bounds);
471    }
472
473    fn paint(&self, text: &str, window: &mut Window, cx: &mut App) {
474        let element_state = self.0.borrow();
475        let element_state = element_state
476            .as_ref()
477            .with_context(|| format!("measurement has not been performed on {text}"))
478            .unwrap();
479        let bounds = element_state
480            .bounds
481            .with_context(|| format!("prepaint has not been performed on {text}"))
482            .unwrap();
483
484        let line_height = element_state.line_height;
485        let mut line_origin = bounds.origin;
486        let text_style = window.text_style();
487        for line in &element_state.lines {
488            line.paint_background(
489                line_origin,
490                line_height,
491                text_style.text_align,
492                Some(bounds),
493                window,
494                cx,
495            )
496            .log_err();
497            line.paint(
498                line_origin,
499                line_height,
500                text_style.text_align,
501                Some(bounds),
502                window,
503                cx,
504            )
505            .log_err();
506            line_origin.y += line.size(line_height).height;
507        }
508    }
509
510    /// Get the byte index into the input of the pixel position.
511    pub fn index_for_position(&self, mut position: Point<Pixels>) -> Result<usize, usize> {
512        let element_state = self.0.borrow();
513        let element_state = element_state
514            .as_ref()
515            .expect("measurement has not been performed");
516        let bounds = element_state
517            .bounds
518            .expect("prepaint has not been performed");
519
520        if position.y < bounds.top() {
521            return Err(0);
522        }
523
524        let line_height = element_state.line_height;
525        let mut line_origin = bounds.origin;
526        let mut line_start_ix = 0;
527        for line in &element_state.lines {
528            let line_bottom = line_origin.y + line.size(line_height).height;
529            if position.y > line_bottom {
530                line_origin.y = line_bottom;
531                line_start_ix += line.len() + 1;
532            } else {
533                let position_within_line = position - line_origin;
534                match line.index_for_position(position_within_line, line_height) {
535                    Ok(index_within_line) => return Ok(line_start_ix + index_within_line),
536                    Err(index_within_line) => return Err(line_start_ix + index_within_line),
537                }
538            }
539        }
540
541        Err(line_start_ix.saturating_sub(1))
542    }
543
544    /// Get the pixel position for the given byte index.
545    pub fn position_for_index(&self, index: usize) -> Option<Point<Pixels>> {
546        let element_state = self.0.borrow();
547        let element_state = element_state
548            .as_ref()
549            .expect("measurement has not been performed");
550        let bounds = element_state
551            .bounds
552            .expect("prepaint has not been performed");
553        let line_height = element_state.line_height;
554
555        let mut line_origin = bounds.origin;
556        let mut line_start_ix = 0;
557
558        for line in &element_state.lines {
559            let line_end_ix = line_start_ix + line.len();
560            if index < line_start_ix {
561                break;
562            } else if index > line_end_ix {
563                line_origin.y += line.size(line_height).height;
564                line_start_ix = line_end_ix + 1;
565                continue;
566            } else {
567                let ix_within_line = index - line_start_ix;
568                return Some(line_origin + line.position_for_index(ix_within_line, line_height)?);
569            }
570        }
571
572        None
573    }
574
575    /// Retrieve the layout for the line containing the given byte index.
576    pub fn line_layout_for_index(&self, index: usize) -> Option<Arc<WrappedLineLayout>> {
577        let element_state = self.0.borrow();
578        let element_state = element_state
579            .as_ref()
580            .expect("measurement has not been performed");
581        let bounds = element_state
582            .bounds
583            .expect("prepaint has not been performed");
584        let line_height = element_state.line_height;
585
586        let mut line_origin = bounds.origin;
587        let mut line_start_ix = 0;
588
589        for line in &element_state.lines {
590            let line_end_ix = line_start_ix + line.len();
591            if index < line_start_ix {
592                break;
593            } else if index > line_end_ix {
594                line_origin.y += line.size(line_height).height;
595                line_start_ix = line_end_ix + 1;
596                continue;
597            } else {
598                return Some(line.layout.clone());
599            }
600        }
601
602        None
603    }
604
605    /// The bounds of this layout.
606    pub fn bounds(&self) -> Bounds<Pixels> {
607        self.0.borrow().as_ref().unwrap().bounds.unwrap()
608    }
609
610    /// The line height for this layout.
611    pub fn line_height(&self) -> Pixels {
612        self.0.borrow().as_ref().unwrap().line_height
613    }
614
615    /// The UTF-8 length of the underlying text.
616    pub fn len(&self) -> usize {
617        self.0.borrow().as_ref().unwrap().len
618    }
619
620    /// The text for this layout.
621    pub fn text(&self) -> String {
622        self.0
623            .borrow()
624            .as_ref()
625            .unwrap()
626            .lines
627            .iter()
628            .map(|s| s.text.to_string())
629            .collect::<Vec<_>>()
630            .join("\n")
631    }
632
633    /// The text for this layout (with soft-wraps as newlines)
634    pub fn wrapped_text(&self) -> String {
635        let mut lines = Vec::new();
636        for wrapped in self.0.borrow().as_ref().unwrap().lines.iter() {
637            let mut seen = 0;
638            for boundary in wrapped.layout.wrap_boundaries.iter() {
639                let index = wrapped.layout.unwrapped_layout.runs[boundary.run_ix].glyphs
640                    [boundary.glyph_ix]
641                    .index;
642
643                lines.push(wrapped.text[seen..index].to_string());
644                seen = index;
645            }
646            lines.push(wrapped.text[seen..].to_string());
647        }
648
649        lines.join("\n")
650    }
651}
652
653/// A text element that can be interacted with.
654pub struct InteractiveText {
655    element_id: ElementId,
656    text: StyledText,
657    click_listener:
658        Option<Box<dyn Fn(&[Range<usize>], InteractiveTextClickEvent, &mut Window, &mut App)>>,
659    hover_listener: Option<Box<dyn Fn(Option<usize>, MouseMoveEvent, &mut Window, &mut App)>>,
660    tooltip_builder: Option<Rc<dyn Fn(usize, &mut Window, &mut App) -> Option<AnyView>>>,
661    tooltip_id: Option<TooltipId>,
662    clickable_ranges: Vec<Range<usize>>,
663}
664
665struct InteractiveTextClickEvent {
666    mouse_down_index: usize,
667    mouse_up_index: usize,
668}
669
670#[doc(hidden)]
671#[derive(Default)]
672pub struct InteractiveTextState {
673    mouse_down_index: Rc<Cell<Option<usize>>>,
674    hovered_index: Rc<Cell<Option<usize>>>,
675    active_tooltip: Rc<RefCell<Option<ActiveTooltip>>>,
676}
677
678/// InteractiveTest is a wrapper around StyledText that adds mouse interactions.
679impl InteractiveText {
680    /// Creates a new InteractiveText from the given text.
681    pub fn new(id: impl Into<ElementId>, text: StyledText) -> Self {
682        Self {
683            element_id: id.into(),
684            text,
685            click_listener: None,
686            hover_listener: None,
687            tooltip_builder: None,
688            tooltip_id: None,
689            clickable_ranges: Vec::new(),
690        }
691    }
692
693    /// on_click is called when the user clicks on one of the given ranges, passing the index of
694    /// the clicked range.
695    pub fn on_click(
696        mut self,
697        ranges: Vec<Range<usize>>,
698        listener: impl Fn(usize, &mut Window, &mut App) + 'static,
699    ) -> Self {
700        self.click_listener = Some(Box::new(move |ranges, event, window, cx| {
701            for (range_ix, range) in ranges.iter().enumerate() {
702                if range.contains(&event.mouse_down_index) && range.contains(&event.mouse_up_index)
703                {
704                    listener(range_ix, window, cx);
705                }
706            }
707        }));
708        self.clickable_ranges = ranges;
709        self
710    }
711
712    /// on_hover is called when the mouse moves over a character within the text, passing the
713    /// index of the hovered character, or None if the mouse leaves the text.
714    pub fn on_hover(
715        mut self,
716        listener: impl Fn(Option<usize>, MouseMoveEvent, &mut Window, &mut App) + 'static,
717    ) -> Self {
718        self.hover_listener = Some(Box::new(listener));
719        self
720    }
721
722    /// tooltip lets you specify a tooltip for a given character index in the string.
723    pub fn tooltip(
724        mut self,
725        builder: impl Fn(usize, &mut Window, &mut App) -> Option<AnyView> + 'static,
726    ) -> Self {
727        self.tooltip_builder = Some(Rc::new(builder));
728        self
729    }
730}
731
732impl Element for InteractiveText {
733    type RequestLayoutState = ();
734    type PrepaintState = Hitbox;
735
736    fn id(&self) -> Option<ElementId> {
737        Some(self.element_id.clone())
738    }
739
740    fn source_location(&self) -> Option<&'static core::panic::Location<'static>> {
741        None
742    }
743
744    fn a11y_role(&self) -> Option<accesskit::Role> {
745        Some(accesskit::Role::Label)
746    }
747
748    fn write_a11y_info(&self, node: &mut accesskit::Node) {
749        node.set_value(self.text.text.to_string());
750    }
751
752    fn request_layout(
753        &mut self,
754        _id: Option<&GlobalElementId>,
755        inspector_id: Option<&InspectorElementId>,
756        window: &mut Window,
757        cx: &mut App,
758    ) -> (LayoutId, Self::RequestLayoutState) {
759        self.text.request_layout(None, inspector_id, window, cx)
760    }
761
762    fn prepaint(
763        &mut self,
764        global_id: Option<&GlobalElementId>,
765        inspector_id: Option<&InspectorElementId>,
766        bounds: Bounds<Pixels>,
767        state: &mut Self::RequestLayoutState,
768        window: &mut Window,
769        cx: &mut App,
770    ) -> Hitbox {
771        window.with_optional_element_state::<InteractiveTextState, _>(
772            global_id,
773            |interactive_state, window| {
774                let mut interactive_state = interactive_state
775                    .map(|interactive_state| interactive_state.unwrap_or_default());
776
777                if let Some(interactive_state) = interactive_state.as_mut() {
778                    if self.tooltip_builder.is_some() {
779                        self.tooltip_id =
780                            set_tooltip_on_window(&interactive_state.active_tooltip, window);
781                    } else {
782                        // If there is no longer a tooltip builder, remove the active tooltip.
783                        interactive_state.active_tooltip.take();
784                    }
785                }
786
787                self.text
788                    .prepaint(None, inspector_id, bounds, state, window, cx);
789                let hitbox = window.insert_hitbox(bounds, HitboxBehavior::Normal);
790                (hitbox, interactive_state)
791            },
792        )
793    }
794
795    fn paint(
796        &mut self,
797        global_id: Option<&GlobalElementId>,
798        inspector_id: Option<&InspectorElementId>,
799        bounds: Bounds<Pixels>,
800        _: &mut Self::RequestLayoutState,
801        hitbox: &mut Hitbox,
802        window: &mut Window,
803        cx: &mut App,
804    ) {
805        let current_view = window.current_view();
806        let text_layout = self.text.layout().clone();
807        window.with_element_state::<InteractiveTextState, _>(
808            global_id.unwrap(),
809            |interactive_state, window| {
810                let mut interactive_state = interactive_state.unwrap_or_default();
811                if let Some(click_listener) = self.click_listener.take() {
812                    let mouse_position = window.mouse_position();
813                    if let Ok(ix) = text_layout.index_for_position(mouse_position)
814                        && self
815                            .clickable_ranges
816                            .iter()
817                            .any(|range| range.contains(&ix))
818                    {
819                        window.set_cursor_style(crate::CursorStyle::PointingHand, hitbox)
820                    }
821
822                    let text_layout = text_layout.clone();
823                    let mouse_down = interactive_state.mouse_down_index.clone();
824                    if let Some(mouse_down_index) = mouse_down.get() {
825                        let hitbox = hitbox.clone();
826                        let clickable_ranges = mem::take(&mut self.clickable_ranges);
827                        window.on_mouse_event(
828                            move |event: &MouseUpEvent, phase, window: &mut Window, cx| {
829                                if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
830                                    if let Ok(mouse_up_index) =
831                                        text_layout.index_for_position(event.position)
832                                    {
833                                        click_listener(
834                                            &clickable_ranges,
835                                            InteractiveTextClickEvent {
836                                                mouse_down_index,
837                                                mouse_up_index,
838                                            },
839                                            window,
840                                            cx,
841                                        )
842                                    }
843
844                                    mouse_down.take();
845                                    window.refresh();
846                                }
847                            },
848                        );
849                    } else {
850                        let hitbox = hitbox.clone();
851                        window.on_mouse_event(move |event: &MouseDownEvent, phase, window, _| {
852                            if phase == DispatchPhase::Bubble
853                                && hitbox.is_hovered(window)
854                                && let Ok(mouse_down_index) =
855                                    text_layout.index_for_position(event.position)
856                            {
857                                mouse_down.set(Some(mouse_down_index));
858                                window.refresh();
859                            }
860                        });
861                    }
862                }
863
864                window.on_mouse_event({
865                    let mut hover_listener = self.hover_listener.take();
866                    let hitbox = hitbox.clone();
867                    let text_layout = text_layout.clone();
868                    let hovered_index = interactive_state.hovered_index.clone();
869                    move |event: &MouseMoveEvent, phase, window, cx| {
870                        if phase == DispatchPhase::Bubble && hitbox.is_hovered(window) {
871                            let current = hovered_index.get();
872                            let updated = text_layout.index_for_position(event.position).ok();
873                            if current != updated {
874                                hovered_index.set(updated);
875                                if let Some(hover_listener) = hover_listener.as_ref() {
876                                    hover_listener(updated, event.clone(), window, cx);
877                                }
878                                cx.notify(current_view);
879                            }
880                        }
881                    }
882                });
883
884                if let Some(tooltip_builder) = self.tooltip_builder.clone() {
885                    let active_tooltip = interactive_state.active_tooltip.clone();
886                    let build_tooltip = Rc::new({
887                        let tooltip_is_hoverable = false;
888                        let text_layout = text_layout.clone();
889                        move |window: &mut Window, cx: &mut App| {
890                            text_layout
891                                .index_for_position(window.mouse_position())
892                                .ok()
893                                .and_then(|position| tooltip_builder(position, window, cx))
894                                .map(|view| (view, tooltip_is_hoverable))
895                        }
896                    });
897
898                    // Use bounds instead of testing hitbox since this is called during prepaint.
899                    let check_is_hovered_during_prepaint = Rc::new({
900                        let source_bounds = hitbox.bounds;
901                        let text_layout = text_layout.clone();
902                        let pending_mouse_down = interactive_state.mouse_down_index.clone();
903                        move |window: &Window| {
904                            text_layout
905                                .index_for_position(window.mouse_position())
906                                .is_ok()
907                                && source_bounds.contains(&window.mouse_position())
908                                && pending_mouse_down.get().is_none()
909                        }
910                    });
911
912                    let check_is_hovered = Rc::new({
913                        let hitbox = hitbox.clone();
914                        let text_layout = text_layout.clone();
915                        let pending_mouse_down = interactive_state.mouse_down_index.clone();
916                        move |window: &Window| {
917                            text_layout
918                                .index_for_position(window.mouse_position())
919                                .is_ok()
920                                && hitbox.is_hovered(window)
921                                && pending_mouse_down.get().is_none()
922                        }
923                    });
924
925                    register_tooltip_mouse_handlers(
926                        &active_tooltip,
927                        self.tooltip_id,
928                        build_tooltip,
929                        check_is_hovered,
930                        check_is_hovered_during_prepaint,
931                        None,
932                        window,
933                    );
934                }
935
936                self.text
937                    .paint(None, inspector_id, bounds, &mut (), &mut (), window, cx);
938
939                ((), interactive_state)
940            },
941        );
942    }
943}
944
945impl IntoElement for InteractiveText {
946    type Element = Self;
947
948    fn into_element(self) -> Self::Element {
949        self
950    }
951}
952
953#[cfg(test)]
954mod tests {
955    use super::*;
956    use crate::{px, size};
957
958    #[test]
959    fn truncated_layout_is_not_reused_for_an_unconstrained_measurement() {
960        let cached = TextLayoutInner {
961            len: 4,
962            lines: SmallVec::new(),
963            line_height: px(16.0),
964            wrap_width: None,
965            truncate_width: Some(px(24.0)),
966            size: Some(size(px(24.0), px(16.0))),
967            bounds: None,
968        };
969
970        assert_eq!(cached_size_for_constraints(&cached, None, None), None);
971    }
972
973    #[test]
974    fn exact_fit_shaped_text_does_not_require_truncation() {
975        assert!(all_shaped_line_widths_fit([px(72.0), px(80.0)], px(80.0)));
976        assert!(!all_shaped_line_widths_fit([px(80.5)], px(80.0)));
977    }
978}