1use std::{any::TypeId, rc::Rc};
2
3use super::Padding;
4use crate::{
5 geometry::{
6 rect::RectF,
7 vector::{vec2f, Vector2F},
8 },
9 platform::CursorStyle,
10 scene::CursorRegion,
11 DebugContext, Element, ElementBox, Event, EventContext, LayoutContext, MouseRegion, MouseState,
12 PaintContext, RenderContext, SizeConstraint, View,
13};
14use serde_json::json;
15
16pub struct MouseEventHandler {
17 child: ElementBox,
18 tag: TypeId,
19 id: usize,
20 cursor_style: Option<CursorStyle>,
21 mouse_down: Option<Rc<dyn Fn(Vector2F, &mut EventContext)>>,
22 click: Option<Rc<dyn Fn(Vector2F, usize, &mut EventContext)>>,
23 right_mouse_down: Option<Rc<dyn Fn(Vector2F, &mut EventContext)>>,
24 right_click: Option<Rc<dyn Fn(Vector2F, usize, &mut EventContext)>>,
25 mouse_down_out: Option<Rc<dyn Fn(Vector2F, &mut EventContext)>>,
26 right_mouse_down_out: Option<Rc<dyn Fn(Vector2F, &mut EventContext)>>,
27 drag: Option<Rc<dyn Fn(Vector2F, &mut EventContext)>>,
28 padding: Padding,
29}
30
31impl MouseEventHandler {
32 pub fn new<Tag, V, F>(id: usize, cx: &mut RenderContext<V>, render_child: F) -> Self
33 where
34 Tag: 'static,
35 V: View,
36 F: FnOnce(MouseState, &mut RenderContext<V>) -> ElementBox,
37 {
38 Self {
39 id,
40 tag: TypeId::of::<Tag>(),
41 child: render_child(cx.mouse_state::<Tag>(id), cx),
42 cursor_style: None,
43 mouse_down: None,
44 click: None,
45 right_mouse_down: None,
46 right_click: None,
47 mouse_down_out: None,
48 right_mouse_down_out: None,
49 drag: None,
50 padding: Default::default(),
51 }
52 }
53
54 pub fn with_cursor_style(mut self, cursor: CursorStyle) -> Self {
55 self.cursor_style = Some(cursor);
56 self
57 }
58
59 pub fn on_mouse_down(
60 mut self,
61 handler: impl Fn(Vector2F, &mut EventContext) + 'static,
62 ) -> Self {
63 self.mouse_down = Some(Rc::new(handler));
64 self
65 }
66
67 pub fn on_click(
68 mut self,
69 handler: impl Fn(Vector2F, usize, &mut EventContext) + 'static,
70 ) -> Self {
71 self.click = Some(Rc::new(handler));
72 self
73 }
74
75 pub fn on_right_mouse_down(
76 mut self,
77 handler: impl Fn(Vector2F, &mut EventContext) + 'static,
78 ) -> Self {
79 self.right_mouse_down = Some(Rc::new(handler));
80 self
81 }
82
83 pub fn on_right_click(
84 mut self,
85 handler: impl Fn(Vector2F, usize, &mut EventContext) + 'static,
86 ) -> Self {
87 self.right_click = Some(Rc::new(handler));
88 self
89 }
90
91 pub fn on_drag(mut self, handler: impl Fn(Vector2F, &mut EventContext) + 'static) -> Self {
92 self.drag = Some(Rc::new(handler));
93 self
94 }
95
96 pub fn with_padding(mut self, padding: Padding) -> Self {
97 self.padding = padding;
98 self
99 }
100
101 fn hit_bounds(&self, bounds: RectF) -> RectF {
102 RectF::from_points(
103 bounds.origin() - vec2f(self.padding.left, self.padding.top),
104 bounds.lower_right() + vec2f(self.padding.right, self.padding.bottom),
105 )
106 .round_out()
107 }
108}
109
110impl Element for MouseEventHandler {
111 type LayoutState = ();
112 type PaintState = ();
113
114 fn layout(
115 &mut self,
116 constraint: SizeConstraint,
117 cx: &mut LayoutContext,
118 ) -> (Vector2F, Self::LayoutState) {
119 (self.child.layout(constraint, cx), ())
120 }
121
122 fn paint(
123 &mut self,
124 bounds: RectF,
125 visible_bounds: RectF,
126 _: &mut Self::LayoutState,
127 cx: &mut PaintContext,
128 ) -> Self::PaintState {
129 if let Some(style) = self.cursor_style {
130 cx.scene.push_cursor_region(CursorRegion {
131 bounds: self.hit_bounds(bounds),
132 style,
133 });
134 }
135
136 cx.scene.push_mouse_region(MouseRegion {
137 view_id: cx.current_view_id(),
138 discriminant: Some((self.tag, self.id)),
139 bounds: self.hit_bounds(bounds),
140 hover: None,
141 click: self.click.clone(),
142 mouse_down: self.mouse_down.clone(),
143 right_click: self.right_click.clone(),
144 right_mouse_down: self.right_mouse_down.clone(),
145 mouse_down_out: self.mouse_down_out.clone(),
146 right_mouse_down_out: self.right_mouse_down_out.clone(),
147 drag: self.drag.clone(),
148 });
149
150 self.child.paint(bounds.origin(), visible_bounds, cx);
151 }
152
153 fn dispatch_event(
154 &mut self,
155 event: &Event,
156 _: RectF,
157 _: RectF,
158 _: &mut Self::LayoutState,
159 _: &mut Self::PaintState,
160 cx: &mut EventContext,
161 ) -> bool {
162 self.child.dispatch_event(event, cx)
163 }
164
165 fn debug(
166 &self,
167 _: RectF,
168 _: &Self::LayoutState,
169 _: &Self::PaintState,
170 cx: &DebugContext,
171 ) -> serde_json::Value {
172 json!({
173 "type": "MouseEventHandler",
174 "child": self.child.debug(cx),
175 })
176 }
177}