1use super::{
2 ContainerStyle, Element, ElementBox, Flex, KeystrokeLabel, MouseEventHandler, Overlay,
3 OverlayFitMode, ParentElement, Text,
4};
5use crate::{
6 fonts::TextStyle,
7 geometry::{rect::RectF, vector::Vector2F},
8 json::json,
9 Action, Axis, ElementStateHandle, SceneBuilder, SizeConstraint, Task, View, ViewContext,
10};
11use serde::Deserialize;
12use std::{
13 cell::{Cell, RefCell},
14 ops::Range,
15 rc::Rc,
16 time::Duration,
17};
18
19const DEBOUNCE_TIMEOUT: Duration = Duration::from_millis(500);
20
21pub struct Tooltip<V: View> {
22 child: ElementBox<V>,
23 tooltip: Option<ElementBox<V>>,
24 _state: ElementStateHandle<Rc<TooltipState>>,
25}
26
27#[derive(Default)]
28struct TooltipState {
29 visible: Cell<bool>,
30 position: Cell<Vector2F>,
31 debounce: RefCell<Option<Task<()>>>,
32}
33
34#[derive(Clone, Deserialize, Default)]
35pub struct TooltipStyle {
36 #[serde(flatten)]
37 pub container: ContainerStyle,
38 pub text: TextStyle,
39 keystroke: KeystrokeStyle,
40 pub max_text_width: f32,
41}
42
43#[derive(Clone, Deserialize, Default)]
44pub struct KeystrokeStyle {
45 #[serde(flatten)]
46 container: ContainerStyle,
47 #[serde(flatten)]
48 text: TextStyle,
49}
50
51impl<V: View> Tooltip<V> {
52 pub fn new<Tag: 'static, T: View>(
53 id: usize,
54 text: String,
55 action: Option<Box<dyn Action>>,
56 style: TooltipStyle,
57 child: ElementBox<V>,
58 view: &mut V,
59 cx: &mut ViewContext<V>,
60 ) -> Self {
61 struct ElementState<Tag>(Tag);
62 struct MouseEventHandlerState<Tag>(Tag);
63 let focused_view_id = cx.focused_view_id();
64
65 let state_handle = cx.default_element_state::<ElementState<Tag>, Rc<TooltipState>>(id);
66 let state = state_handle.read(cx).clone();
67 let tooltip = if state.visible.get() {
68 let mut collapsed_tooltip = Self::render_tooltip(
69 cx.window_id,
70 focused_view_id,
71 text.clone(),
72 style.clone(),
73 action.as_ref().map(|a| a.boxed_clone()),
74 true,
75 )
76 .boxed();
77 Some(
78 Overlay::new(
79 Self::render_tooltip(cx.window_id, focused_view_id, text, style, action, false)
80 .constrained()
81 .dynamically(move |constraint, cx| {
82 SizeConstraint::strict_along(
83 Axis::Vertical,
84 collapsed_tooltip.layout(constraint, cx).y(),
85 )
86 })
87 .boxed(),
88 )
89 .with_fit_mode(OverlayFitMode::SwitchAnchor)
90 .with_anchor_position(state.position.get())
91 .boxed(),
92 )
93 } else {
94 None
95 };
96 let child =
97 MouseEventHandler::<MouseEventHandlerState<Tag>>::new(id, view, cx, |_, _| child)
98 .on_hover(move |e, cx| {
99 let position = e.position;
100 let window_id = cx.window_id();
101 if let Some(view_id) = cx.view_id() {
102 if e.started {
103 if !state.visible.get() {
104 state.position.set(position);
105
106 let mut debounce = state.debounce.borrow_mut();
107 if debounce.is_none() {
108 *debounce = Some(cx.spawn({
109 let state = state.clone();
110 |mut cx| async move {
111 cx.background().timer(DEBOUNCE_TIMEOUT).await;
112 state.visible.set(true);
113 cx.update(|cx| cx.notify_view(window_id, view_id));
114 }
115 }));
116 }
117 }
118 } else {
119 state.visible.set(false);
120 state.debounce.take();
121 cx.notify();
122 }
123 }
124 })
125 .boxed();
126 Self {
127 child,
128 tooltip,
129 _state: state_handle,
130 }
131 }
132
133 pub fn render_tooltip(
134 window_id: usize,
135 focused_view_id: Option<usize>,
136 text: String,
137 style: TooltipStyle,
138 action: Option<Box<dyn Action>>,
139 measure: bool,
140 ) -> impl Element {
141 Flex::row()
142 .with_child({
143 let text = Text::new(text, style.text)
144 .constrained()
145 .with_max_width(style.max_text_width);
146 if measure {
147 text.flex(1., false).boxed()
148 } else {
149 text.flex(1., false).aligned().boxed()
150 }
151 })
152 .with_children(action.and_then(|action| {
153 let keystroke_label = KeystrokeLabel::new(
154 window_id,
155 focused_view_id?,
156 action,
157 style.keystroke.container,
158 style.keystroke.text,
159 );
160 if measure {
161 Some(keystroke_label.boxed())
162 } else {
163 Some(keystroke_label.aligned().boxed())
164 }
165 }))
166 .contained()
167 .with_style(style.container)
168 }
169}
170
171impl<V: View> Element<V> for Tooltip<V> {
172 type LayoutState = ();
173 type PaintState = ();
174
175 fn layout(
176 &mut self,
177 constraint: SizeConstraint,
178 view: &mut V,
179 cx: &mut ViewContext<V>,
180 ) -> (Vector2F, Self::LayoutState) {
181 let size = self.child.layout(constraint, view, cx);
182 if let Some(tooltip) = self.tooltip.as_mut() {
183 tooltip.layout(
184 SizeConstraint::new(Vector2F::zero(), cx.window_size),
185 view,
186 cx,
187 );
188 }
189 (size, ())
190 }
191
192 fn paint(
193 &mut self,
194 scene: &mut SceneBuilder,
195 bounds: RectF,
196 visible_bounds: RectF,
197 _: &mut Self::LayoutState,
198 view: &mut V,
199 cx: &mut ViewContext<V>,
200 ) {
201 self.child
202 .paint(scene, bounds.origin(), visible_bounds, view, cx);
203 if let Some(tooltip) = self.tooltip.as_mut() {
204 tooltip.paint(scene, bounds.origin(), visible_bounds, view, cx);
205 }
206 }
207
208 fn rect_for_text_range(
209 &self,
210 range: Range<usize>,
211 _: RectF,
212 _: RectF,
213 _: &Self::LayoutState,
214 _: &Self::PaintState,
215 view: &V,
216 cx: &ViewContext<V>,
217 ) -> Option<RectF> {
218 self.child.rect_for_text_range(range, view, cx)
219 }
220
221 fn debug(
222 &self,
223 _: RectF,
224 _: &Self::LayoutState,
225 _: &Self::PaintState,
226 view: &V,
227 cx: &ViewContext<V>,
228 ) -> serde_json::Value {
229 json!({
230 "child": self.child.debug(view, cx),
231 "tooltip": self.tooltip.as_ref().map(|t| t.debug(view, cx)),
232 })
233 }
234}