1use super::{
2 ContainerStyle, Drawable, Element, 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: Element<V>,
23 tooltip: Option<Element<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: Element<V>,
58 cx: &mut ViewContext<V>,
59 ) -> Self {
60 struct ElementState<Tag>(Tag);
61 struct MouseEventHandlerState<Tag>(Tag);
62 let focused_view_id = cx.focused_view_id();
63
64 let state_handle = cx.default_element_state::<ElementState<Tag>, Rc<TooltipState>>(id);
65 let state = state_handle.read(cx).clone();
66 let tooltip = if state.visible.get() {
67 let mut collapsed_tooltip = Self::render_tooltip(
68 cx.window_id,
69 focused_view_id,
70 text.clone(),
71 style.clone(),
72 action.as_ref().map(|a| a.boxed_clone()),
73 true,
74 )
75 .boxed();
76 Some(
77 Overlay::new(
78 Self::render_tooltip(cx.window_id, focused_view_id, text, style, action, false)
79 .constrained()
80 .dynamically(move |constraint, view, cx| {
81 SizeConstraint::strict_along(
82 Axis::Vertical,
83 collapsed_tooltip.layout(constraint, view, cx).y(),
84 )
85 })
86 .boxed(),
87 )
88 .with_fit_mode(OverlayFitMode::SwitchAnchor)
89 .with_anchor_position(state.position.get())
90 .boxed(),
91 )
92 } else {
93 None
94 };
95 let child = MouseEventHandler::<MouseEventHandlerState<Tag>, _>::new(id, cx, |_, _| child)
96 .on_hover(move |e, _, cx| {
97 let position = e.position;
98 let window_id = cx.window_id();
99 let view_id = cx.view_id();
100 if e.started {
101 if !state.visible.get() {
102 state.position.set(position);
103
104 let mut debounce = state.debounce.borrow_mut();
105 if debounce.is_none() {
106 *debounce = Some(cx.spawn({
107 let state = state.clone();
108 |_, mut cx| async move {
109 cx.background().timer(DEBOUNCE_TIMEOUT).await;
110 state.visible.set(true);
111 cx.update(|cx| cx.notify_view(window_id, view_id));
112 }
113 }));
114 }
115 }
116 } else {
117 state.visible.set(false);
118 state.debounce.take();
119 cx.notify();
120 }
121 })
122 .boxed();
123 Self {
124 child,
125 tooltip,
126 _state: state_handle,
127 }
128 }
129
130 pub fn render_tooltip(
131 window_id: usize,
132 focused_view_id: Option<usize>,
133 text: String,
134 style: TooltipStyle,
135 action: Option<Box<dyn Action>>,
136 measure: bool,
137 ) -> impl Drawable<V> {
138 Flex::row()
139 .with_child({
140 let text = Text::new(text, style.text)
141 .constrained()
142 .with_max_width(style.max_text_width);
143 if measure {
144 text.flex(1., false).boxed()
145 } else {
146 text.flex(1., false).aligned().boxed()
147 }
148 })
149 .with_children(action.and_then(|action| {
150 let keystroke_label = KeystrokeLabel::new(
151 window_id,
152 focused_view_id?,
153 action,
154 style.keystroke.container,
155 style.keystroke.text,
156 );
157 if measure {
158 Some(keystroke_label.boxed())
159 } else {
160 Some(keystroke_label.aligned().boxed())
161 }
162 }))
163 .contained()
164 .with_style(style.container)
165 }
166}
167
168impl<V: View> Drawable<V> for Tooltip<V> {
169 type LayoutState = ();
170 type PaintState = ();
171
172 fn layout(
173 &mut self,
174 constraint: SizeConstraint,
175 view: &mut V,
176 cx: &mut ViewContext<V>,
177 ) -> (Vector2F, Self::LayoutState) {
178 let size = self.child.layout(constraint, view, cx);
179 if let Some(tooltip) = self.tooltip.as_mut() {
180 tooltip.layout(
181 SizeConstraint::new(Vector2F::zero(), cx.window_size()),
182 view,
183 cx,
184 );
185 }
186 (size, ())
187 }
188
189 fn paint(
190 &mut self,
191 scene: &mut SceneBuilder,
192 bounds: RectF,
193 visible_bounds: RectF,
194 _: &mut Self::LayoutState,
195 view: &mut V,
196 cx: &mut ViewContext<V>,
197 ) {
198 self.child
199 .paint(scene, bounds.origin(), visible_bounds, view, cx);
200 if let Some(tooltip) = self.tooltip.as_mut() {
201 tooltip.paint(scene, bounds.origin(), visible_bounds, view, cx);
202 }
203 }
204
205 fn rect_for_text_range(
206 &self,
207 range: Range<usize>,
208 _: RectF,
209 _: RectF,
210 _: &Self::LayoutState,
211 _: &Self::PaintState,
212 view: &V,
213 cx: &ViewContext<V>,
214 ) -> Option<RectF> {
215 self.child.rect_for_text_range(range, view, cx)
216 }
217
218 fn debug(
219 &self,
220 _: RectF,
221 _: &Self::LayoutState,
222 _: &Self::PaintState,
223 view: &V,
224 cx: &ViewContext<V>,
225 ) -> serde_json::Value {
226 json!({
227 "child": self.child.debug(view, cx),
228 "tooltip": self.tooltip.as_ref().map(|t| t.debug(view, cx)),
229 })
230 }
231}