cursive_tree/view/
view.rs

1use super::{
2    super::{backend::*, model::*},
3    tree::*,
4};
5
6use cursive::{direction::*, event::*, theme::*, view::*, *};
7
8const TYPE_NAME: &str = "TreeView";
9
10impl<BackendT> View for TreeView<BackendT>
11where
12    BackendT: 'static + TreeBackend + Send + Sync,
13    BackendT::Context: Clone + Send + Sync,
14    BackendT::Error: Send + Sync,
15    BackendT::ID: Send + Sync,
16    BackendT::Data: Send + Sync,
17{
18    fn type_name(&self) -> &'static str {
19        TYPE_NAME
20    }
21
22    fn take_focus(&mut self, _source: Direction) -> Result<EventResult, CannotFocus> {
23        if self.model.is_empty() { Err(CannotFocus) } else { Ok(EventResult::consumed()) }
24    }
25
26    fn required_size(&mut self, _constraint: Vec2) -> Vec2 {
27        self.model.extents()
28    }
29
30    fn important_area(&self, view_size: Vec2) -> Rect {
31        if let Some(selected_row) = self.selected_row {
32            Rect::from_size((0, selected_row), (view_size.x, 1))
33        } else {
34            Rect::from_size((0, 0), view_size)
35        }
36    }
37
38    fn on_event(&mut self, event: Event) -> EventResult {
39        let selected_row = self.selected_row;
40
41        match event {
42            Event::Key(Key::Up) => self.move_selection(-1),
43            Event::Key(Key::Down) => self.move_selection(1),
44            Event::Key(Key::PageUp) => self.move_selection(-(self.page as isize)),
45            Event::Key(Key::PageDown) => self.move_selection(self.page as isize),
46            Event::Key(Key::Home) => self.select_top(),
47            Event::Key(Key::End) => self.select_bottom(),
48
49            Event::Key(Key::Left) => {
50                if let Some(node) = self.selected_node_mut()
51                    && node.kind.is_branch()
52                {
53                    node.collapse();
54                }
55            }
56
57            Event::Key(Key::Right) => {
58                let context = self.model.context.clone();
59                if let Some(node) = self.selected_node_mut()
60                    && node.kind.is_branch()
61                {
62                    return Self::on_expand_branch(node, context);
63                }
64            }
65
66            Event::Key(Key::Enter) => {
67                let context = self.model.context.clone();
68                if let Some(node) = self.selected_node_mut()
69                    && node.kind.is_branch()
70                {
71                    return Self::on_toggle_branch_state(node, context);
72                }
73            }
74
75            Event::Mouse { offset, position, event: MouseEvent::Press(_) } => {
76                self.selected_row = if let Some(position) = position.checked_sub(offset)
77                    && let Some(node) = self.model.at_row(position.y)
78                {
79                    if node.kind.is_branch() && (position.x < node.depth * 2 + 2) {
80                        // If we click to the left of the representation then toggle state
81                        let context = self.model.context.clone();
82                        if let Some(path) = self.model.path(node)
83                            && let Some(node) = self.model.at_path_mut(path)
84                        {
85                            return Self::on_toggle_branch_state(node, context);
86                        } else {
87                            None
88                        }
89                    } else {
90                        // Otherwise just select
91                        Some(position.y)
92                    }
93                } else {
94                    None
95                };
96            }
97
98            _ => return EventResult::Ignored,
99        }
100
101        EventResult::Consumed(if self.selected_row != selected_row {
102            // Selection has changed
103            Some(Callback::from_fn_once(|cursive| {
104                BackendT::handle_selection_changed(cursive);
105            }))
106        } else {
107            None
108        })
109    }
110
111    fn draw(&self, printer: &Printer) {
112        let mut start = Vec2::default();
113        for node in self.model.iter(true) {
114            if start.y >= printer.offset.y + printer.size.y {
115                // We're beyond the print area
116                break;
117            }
118
119            // Start printing only when we're within the print area
120            if start.y >= printer.content_offset.y {
121                // Symbol
122
123                start.x = node.depth * 2;
124                match node.symbol(self.model.context.clone()) {
125                    Symbol::Representation(symbol) => printer.print_styled(start, &symbol),
126                    Symbol::String(symbol) => printer.print(start, symbol),
127                };
128                start.x += 2;
129
130                // Representation
131
132                let mut representation = &node.representation;
133
134                let debug_representation = if self.debug
135                    && let Some(path) = self.model.path(node)
136                {
137                    let path: Vec<_> = path.into_iter().map(|i| i.to_string()).collect();
138                    let mut representation = representation.clone();
139                    representation.append(format!(" {}", path.join(".")));
140                    Some(representation)
141                } else {
142                    None
143                };
144
145                if let Some(debug_representation) = &debug_representation {
146                    representation = debug_representation;
147                }
148
149                let highlight = if self.is_selected(start.y) {
150                    Some(if printer.focused { PaletteStyle::Highlight } else { PaletteStyle::HighlightInactive })
151                } else {
152                    None
153                };
154
155                let print = |printer: &Printer| printer.print_styled(start, representation);
156
157                match highlight {
158                    Some(highlight) => printer.with_style(highlight, print),
159                    None => print(printer),
160                }
161            }
162
163            start.y += node.representation_size.y;
164        }
165    }
166}
cursive_tree/view/view.rs

cursive_tree/view/
view.rs
