agg_gui/widgets/table/
config.rs

1//! Configuration types for the `Table` widget.
2//!
3//! Defines column sizing, row descriptions, cell/header info structs, and
4//! the painter callback type aliases shared by the builder and widget impl.
5
6use std::sync::Arc;
7
8use crate::draw_ctx::DrawCtx;
9use crate::geometry::Rect;
10use crate::text::Font;
11use crate::theme::Visuals;
12
13// ── Configuration types ─────────────────────────────────────────────────────
14
15/// How a column derives its width.
16#[derive(Clone, Copy, Debug)]
17pub enum ColumnSize {
18    Auto(f64),
19    Exact(f64),
20    Remainder { at_least: f64, clip: bool },
21}
22
23#[derive(Clone, Copy, Debug)]
24pub struct TableColumn {
25    pub size: ColumnSize,
26    pub resizable: bool,
27}
28
29impl TableColumn {
30    pub fn auto(initial: f64) -> Self {
31        Self {
32            size: ColumnSize::Auto(initial),
33            resizable: false,
34        }
35    }
36    pub fn exact(w: f64) -> Self {
37        Self {
38            size: ColumnSize::Exact(w),
39            resizable: false,
40        }
41    }
42    pub fn remainder() -> Self {
43        Self {
44            size: ColumnSize::Remainder {
45                at_least: 16.0,
46                clip: false,
47            },
48            resizable: false,
49        }
50    }
51    pub fn at_least(mut self, v: f64) -> Self {
52        if let ColumnSize::Remainder { ref mut at_least, .. } = self.size {
53            *at_least = v;
54        }
55        self
56    }
57    pub fn clip(mut self, on: bool) -> Self {
58        if let ColumnSize::Remainder { ref mut clip, .. } = self.size {
59            *clip = on;
60        }
61        self
62    }
63    pub fn resizable(mut self, on: bool) -> Self {
64        self.resizable = on;
65        self
66    }
67}
68
69/// Minimum width any column can be resized to.
70pub const MIN_COL_W: f64 = 16.0;
71/// Pixel half-width of the resize hit zone around a column's right edge.
72pub const RESIZE_HIT_HALF: f64 = 4.0;
73
74/// Distribute `total_w` across `columns` according to their sizing modes.
75///
76/// `overrides[i] = Some(w)` pins column `i` to the user-resized width and
77/// removes it from the auto/remainder distribution.  `Remainder` columns
78/// share whatever space is left after fixed + overridden columns, never
79/// going below their `at_least`.
80pub fn distribute_widths(
81    columns: &[TableColumn],
82    total_w: f64,
83    overrides: &[Option<f64>],
84) -> Vec<f64> {
85    let n = columns.len();
86    let mut out = vec![0.0_f64; n];
87    let mut remainder_indices: Vec<usize> = Vec::new();
88    let mut remainder_min = 0.0_f64;
89    let mut fixed_total = 0.0_f64;
90    for (i, c) in columns.iter().enumerate() {
91        if let Some(w) = overrides.get(i).copied().flatten() {
92            out[i] = w.max(MIN_COL_W);
93            fixed_total += out[i];
94            continue;
95        }
96        match c.size {
97            ColumnSize::Auto(w) | ColumnSize::Exact(w) => {
98                out[i] = w;
99                fixed_total += w;
100            }
101            ColumnSize::Remainder { at_least, .. } => {
102                remainder_indices.push(i);
103                remainder_min += at_least;
104            }
105        }
106    }
107    let leftover = (total_w - fixed_total).max(remainder_min);
108    if !remainder_indices.is_empty() {
109        let each = leftover / remainder_indices.len() as f64;
110        for &i in &remainder_indices {
111            let at_least = match columns[i].size {
112                ColumnSize::Remainder { at_least, .. } => at_least,
113                _ => 0.0,
114            };
115            out[i] = each.max(at_least);
116        }
117    }
118    out
119}
120
121/// Row-set description.
122#[derive(Clone, Debug)]
123pub enum TableRows {
124    Homogeneous { count: usize, height: f64 },
125    Heterogeneous { heights: Vec<f64> },
126}
127
128impl TableRows {
129    pub fn count(&self) -> usize {
130        match self {
131            TableRows::Homogeneous { count, .. } => *count,
132            TableRows::Heterogeneous { heights } => heights.len(),
133        }
134    }
135    pub fn height_at(&self, i: usize) -> f64 {
136        match self {
137            TableRows::Homogeneous { height, .. } => *height,
138            TableRows::Heterogeneous { heights } => heights.get(i).copied().unwrap_or(0.0),
139        }
140    }
141    pub fn total_height(&self) -> f64 {
142        match self {
143            TableRows::Homogeneous { count, height } => *count as f64 * *height,
144            TableRows::Heterogeneous { heights } => heights.iter().copied().sum(),
145        }
146    }
147    pub fn top_down_y_at(&self, i: usize) -> f64 {
148        match self {
149            TableRows::Homogeneous { height, .. } => i as f64 * *height,
150            TableRows::Heterogeneous { heights } => {
151                let take = i.min(heights.len());
152                heights[..take].iter().copied().sum()
153            }
154        }
155    }
156}
157
158// ── Painter callback shapes ─────────────────────────────────────────────────
159
160pub struct CellInfo<'a> {
161    pub row: usize,
162    pub col: usize,
163    /// Cell rect in widget-local Y-up coordinates of the table body.
164    /// The table has clipped to this rect before invoking the painter.
165    pub rect: Rect,
166    pub selected: bool,
167    pub visuals: &'a Visuals,
168    pub font: &'a Arc<Font>,
169}
170
171pub struct HeaderInfo<'a> {
172    pub col: usize,
173    pub rect: Rect,
174    pub visuals: &'a Visuals,
175    pub font: &'a Arc<Font>,
176}
177
178pub type CellPainter = Box<dyn FnMut(&CellInfo, &mut dyn DrawCtx)>;
179pub type HeaderPainter = Box<dyn FnMut(&HeaderInfo, &mut dyn DrawCtx)>;
180/// Optional callback for header clicks. Receives column index and click
181/// position relative to the header *cell* rect (Y-up).
182pub type HeaderClick = Box<dyn FnMut(usize, f64, f64) -> crate::event::EventResult>;
183/// Per-row predicate (e.g. for overlines).
184pub type RowPredicate = Box<dyn Fn(usize) -> bool>;
185/// Callback returning the live row spec.  Called on every layout pass when
186/// set, so external state changes (e.g. switching demo modes or
187/// resizing the dataset) flow into the table without an observer widget.
188pub type RowsProvider = Box<dyn Fn() -> TableRows>;
agg_gui/widgets/table/config.rs

agg_gui/widgets/table/
config.rs
