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1 //! The immediate-mode renderer for [`makeover_layout`].
2 //!
3 //! <!-- wiki: makeover-immediate -->
4 //!
5 //! Named for the mode, not the library, the way `makeover-tui` is named for
6 //! the target and not for ratatui. Immediate mode is the constraint that
7 //! actually separates this renderer from the other two, and egui is the
8 //! backend it is written against.
9 //!
10 //! It is the harshest renderer the description has to survive: no
11 //! `box-shadow`, no `inset`, no cascade, no retained tree to mutate, and
12 //! `Visuals.widgets.*.bg_stroke` is a single stroke with no per-side control.
13 //! A two-tone lit edge is not something egui can be configured into producing,
14 //! so it gets painted by hand here, once, instead of in every consuming app.
15 //!
16 //! # What this crate does and does not own
17 //!
18 //! It owns the *expression*: two mitred polylines for a bevel and a `Frame`
19 //! for a filled region. It owns no colours and no sizes, and no longer owns a
20 //! substitution: it briefly supplied the page for a well, which was a stand-in
21 //! for `surface-well` before makeover derived it, and every consumer reads the
22 //! real token now. [`Palette`] is supplied by the caller,
23 //! already resolved, and every radius, margin and stroke width arrives in
24 //! [`FrameStyle`].
25 //!
26 //! That split is why the crate has no dependency on `makeover` itself: the app
27 //! already resolves a theme, and coupling a renderer to a colour crate's
28 //! version would buy nothing.
29 //!
30 //! # The cascade is the real difference
31 //!
32 //! A stylesheet can say "a pressed button inverts its bevel" once and let the
33 //! cascade carry it. An immediate-mode renderer has nowhere to put that, so
34 //! every call site decides. [`makeover_layout::Depth::pressed`] is what keeps
35 //! the decision from being re-derived per widget.
36 //!
37 //! # 0.11.0: the overlay becomes reachable
38 //!
39 //! 0.10.0 answered what overlaying means in immediate mode with
40 //! [`Palette::cast`], and nothing could ask: the description had no
41 //! `Depth::Overlay` until `makeover-layout` 0.14.0, so the answer sat beside a
42 //! question that could not be posed. [`frame`] now hands the cast shadow to the
43 //! `egui::Frame` for any depth whose fill is [`Fill::Overlay`], keyed off the
44 //! fill rather than the variant.
45 //!
46 //! The same release brings `makeover_layout::CellPart`, which 0.11.0 carried
47 //! and did not draw. [`table`] draws it, below.
48 //!
49 //! # 0.12.0: the table
50 //!
51 //! [`table`] is the vocabulary 0.11.0 took without using. The consumer is
52 //! audiofiles, whose file list is the only table in the tree exercising all four
53 //! of what the description says about one at once: sortable headings with
54 //! carets, fixed and remainder tracks, and buttons inside cells.
55 //!
56 //! Two things it forces, both named where they land:
57 //!
58 //! - **`egui_extras`**, this crate's first dependency past egui. egui has no
59 //! table, and `Grid` gives no per-column sizing, no sticky header and no
60 //! scroll sync, which is why audiofiles reached for `egui_extras` rather than
61 //! building on `Grid`. A third answer here would reimplement that crate worse.
62 //! - **[`Palette::action`]**, on the footing [`Palette::content`] arrived on: a
63 //! link in a cell is the first thing here needing the action intent.
64 //!
65 //! Narrowing works differently from the terminal's and the module header says
66 //! why: a content column cannot be measured before the app's closure has drawn
67 //! it, so `egui_extras` sizes it and the declared floor budgets it.
68 //!
69 //! # 0.13.0: what the adoption found missing
70 //!
71 //! 0.12.0 shipped [`table`] before audiofiles had taken it, and taking it found
72 //! three things the file list already did that the function could not say. All
73 //! three are host idiom rather than description, which is why they land here and
74 //! not in `makeover-layout`, and all three are answered on a handle the app
75 //! never sees: the `egui_extras` row and builder this crate owns. That is
76 //! [`table::cell`]'s reasoning again: what the app cannot reach, the renderer
77 //! owes it.
78 //!
79 //! - **A selected row.** [`table::Body::selected`], a predicate asked per row,
80 //! because `set_selected` is a method on the row. Without it a file list has
81 //! no way to show what is selected, which is most of what a file list does.
82 //! - **Scrolling a row into view.** [`table::Body::scroll_to`], because
83 //! `scroll_to_row` is a method on the builder. A keyboard cursor that moves
84 //! off-screen and stays there is the bug this prevents.
85 //! - **Dragging a divider.** [`table::TableStyle::resizable`], which passes the
86 //! test `sticky_header` failed in 0.12.0: egui_extras offers two settings here
87 //! and a renderer can honestly make either choice.
88 //!
89 //! A fourth was found and is not a knob. Cells are centred on the row's centre
90 //! line, always, because there is no second honest answer and egui's own default
91 //! (top-aligned) is the one thing it cannot be.
92 //!
93 //! [`table::Body`] is also what splits a table's per-frame facts from its
94 //! description and from its style. A row count, a selection and a scroll request
95 //! are none of them style, and none of them survive the frame.
96 //!
97 //! # 0.18.0: the nodes that were not fields, tables or frames
98 //!
99 //! [`widget`] draws a meter, a token, a control and a figure. `makeover-tui` has
100 //! had all four for releases and this crate had none of them, which stayed
101 //! invisible while the only consumer was an app calling [`field`] and [`table`]
102 //! directly. It stopped being invisible the moment anything tried to draw a
103 //! whole `quasi_router::Screen` in egui: the four are ordinary nodes, so a
104 //! screen walk would have had to draw them itself, one copy per consumer.
105 //!
106 //! [`Palette`] grows the three status intents with it. They arrive together
107 //! rather than one per widget for the reason [`Palette::fill`] is an `Option`:
108 //! `Tone` is five members wide, and a resolver missing one has to invent a
109 //! colour, which is the substitution 0.2.0 spent a release removing.
110 //!
111 //! # Forms
112 //!
113 //! 0.5.0 adds the field vocabulary on top of the depth vocabulary:
114 //! [`makeover_layout::Field`] rendered to egui widgets, in [`field`], and a set
115 //! of them laid down a column in [`group`]. Before it, a description saying
116 //! "text field, labelled, required, with this hint" had no way to become a
117 //! widget here, and audiofiles' forms stayed hand-rolled.
118 //!
119 //! `makeover-webview` got there first and its form emitter is the precedent
120 //! followed rather than re-derived, including the parts that are bug fixes: a
121 //! select handed a value none of its options carries keeps that value visible
122 //! instead of silently reading as the first option, which is a save-the-wrong-
123 //! thing bug goingson hit for real.
124 //!
125 //! What differs is forced by the mode and not chosen:
126 //!
127 //! - **The value arrives as a `&mut`.** [`Filling`] borrows the app's own field
128 //! and the widget writes through it. There is no DOM to read back out of,
129 //! which is also why the description deliberately does not carry the value.
130 //! - **A text control is drawn as a well and a select is not.** The description
131 //! holds that a well is for anything the user looks *into*, and a text field
132 //! is its own example; a select and a checkbox are pressed rather than looked
133 //! into, so they keep egui's own control painting.
134 //! - **Focus is not describable, and egui owns all of it here.** **Reach**,
135 //! **focus** and the **focus ring** are this renderer's three answers and
136 //! egui already has all three: its own id stack decides what is reachable,
137 //! its own state decides what holds the keyboard, and it paints exactly one
138 //! ring. A description states none of them — `makeover_layout` removed the
139 //! member that used to try in 0.19.0 — and drawing a second ring on top of
140 //! egui's would break the one-ring rule it would have come from. The terms
141 //! are defined once in `makeover_layout`'s crate header, "Reach, focus and
142 //! the focus ring". [`makeover_layout::State::Disabled`] *is* drawn, because
143 //! egui has no opinion about it until told.
144 //! - **App-level chrome is not drawn here, and it is not this crate's to
145 //! draw.** `quasi-router` names the affordances that outlive one screen: a
146 //! `Chrome` of key bindings, and an `Outcome::Over` for a screen drawn over
147 //! another. Both are answered by `quasi-webview` and `quasi-tui`, and neither
148 //! is answerable here, because this crate depends on `makeover-layout` and
149 //! not on `quasi-router` — it is the peer of `makeover-webview` and
150 //! `makeover-tui`, one layer below the renderers that consume a `Screen`.
151 //! What is missing is the egui crate at *that* layer, which does not exist:
152 //! nothing renders a quasi `Screen` in egui at all, and chrome is one item on
153 //! the list such a crate would owe. Said here because this is where a reader
154 //! looks for it, and because the silent version reads as "egui does not need
155 //! a palette" rather than "nobody has built the renderer yet".
156
157 //! # 0.31.0: the slider's track is a curve
158 //!
159 //! `makeover-layout` 0.32.0 says what a slider is: a fraction and a function
160 //! taking numbers to numbers, with `min` and `max` being `f(0)` and `f(1)`
161 //! rather than the control's extent. This host has the easiest job of the
162 //! three, because egui already has the control -- `Slider::logarithmic` is a
163 //! constant-ratio track, so the mapping is a builder call rather than an
164 //! arithmetic of its own.
165 //!
166 //! Two things worth knowing. The granularity moved onto the curve, so a range
167 //! reads `Field::curve.step()` and every other kind still reads `Field::step`;
168 //! the step is in the value's own units under either curve, so the display
169 //! precision is derived exactly as before. And the fallback for a ratio curve
170 //! across zero is asked of `Curve::is_ratio` rather than matched on the
171 //! variant, so this renderer and a terminal cannot disagree about when a
172 //! logarithmic request is honoured.
173 //!
174 //! # 0.28.0: the slider, the unanswered chooser, and the option that is not
175 //! offered yet
176 //!
177 //! Three things `makeover-layout` 0.28.0 lets a description say, all three
178 //! found by audiofiles' forms port hitting a wall it could not describe its way
179 //! past.
180 //!
181 //! - **[`FieldKind::Range`] is a fifth control shape**, `Control::Slid`, and
182 //! the first one added since 0.5.0. egui has `Slider` and this crate had no
183 //! way to be asked for one, so four sliders in the only consuming app stayed
184 //! hand-rolled against a vocabulary that could not name them. A range missing
185 //! an end falls back to a well rather than to invented bounds, which is what
186 //! `makeover_layout::Field::bounded` is for.
187 //! - **`Field::placeholder` finally reads on a chooser.** It was sayable and
188 //! this renderer ignored it, so a select with nothing chosen showed an empty
189 //! box. Nothing new is described; the renderer caught up.
190 //! - **`Choice::unavailable` is drawn rather than dropped.** The option stays
191 //! in the list, inert, with its precondition beside it instead of behind a
192 //! hover — a greyed row with no reason reads as a dead end, which is the
193 //! whole finding.
194 //!
195 //! The value still arrives as a `&mut String` and a slider is a number, so the
196 //! parse and the write-back are this renderer's, and the write happens only on
197 //! a real drag: a value the app put there that this host cannot read survives
198 //! being looked at.
199
200 #![forbid(unsafe_code)]
201
202 use egui::{
203 Color32, ComboBox, CornerRadius, Margin, Painter, Rect, Response, RichText, Shape, Slider,
204 Stroke, TextEdit, Ui,
205 };
206 use makeover_layout::{Bevel, Choice, Depth, Edge, Field, FieldKind, Fill, State, Tone};
207 use std::ops::RangeInclusive;
208
209 /// Columns, narrowing, cell parts and the sort caret, over `egui_extras`.
210 pub mod table;
211 pub mod widget;
212
213 /// The resolved colours this renderer needs, as flat values.
214 ///
215 /// Built by the app from whatever it already uses to resolve a theme, then
216 /// held and reused. Deliberately not a trait and not string-keyed: a bevel is
217 /// painted per widget per frame, and a map lookup per edge is a cost with
218 /// nothing to show for it.
219 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
220 pub struct Palette {
221 /// `surface-page`.
222 pub page: Color32,
223 /// `surface-raised`.
224 pub raised: Color32,
225 /// `surface-overlay`.
226 pub overlay: Color32,
227 /// `surface-well`.
228 ///
229 /// Required, not optional. makeover derives it for every theme from 2.3.0,
230 /// so a resolved palette without a well is not a thing that exists here.
231 /// It was an `Option` while that was untrue, and this renderer substituted
232 /// the page; `makeover-tui` keeps its own `Option` for a different reason,
233 /// since a terminal can have the colour and still be unable to show it.
234 pub well: Color32,
235 /// `surface-sunken`.
236 ///
237 /// A surface set back from the one it sits on, by colour and nothing else.
238 /// Not a well: a well is a hole with an edge, and this has no edge. An
239 /// immediate-mode renderer paints an arbitrary rect, so unlike
240 /// `makeover-tui` it has no excuse for declining this one.
241 ///
242 /// Required rather than optional, on the same footing as `well`: all 31
243 /// themes makeover embeds author it.
244 pub sunken: Color32,
245 /// `bevel-light`.
246 pub bevel_light: Color32,
247 /// `bevel-dark`.
248 pub bevel_dark: Color32,
249 /// `elevation`.
250 ///
251 /// What a surface that floats OVER the page is cast onto it with. The one
252 /// intent here that is about a surface's relationship to the page rather
253 /// than about the surface, which is why it is a translucent near-black on
254 /// every theme rather than something read off the palette's own ramp.
255 ///
256 /// **Only for a surface that overlays.** A menu, a tooltip, a modal. A
257 /// surface *in* the layout takes a bevel, and reaching for this on a panel
258 /// or a card is how a pre-Platinum look survives a conversion under a new
259 /// name.
260 ///
261 /// egui has a real answer for this where a terminal does not: see
262 /// [`Palette::cast`], which is the shadow to hand an
263 /// [`egui::Frame`](egui::Frame).
264 pub elevation: Color32,
265 /// `content`.
266 ///
267 /// Ordinary text. Added 0.5.0 with the field renderer, which is the first
268 /// thing here that draws any: until then this crate painted surfaces and
269 /// edges and let the caller's own egui visuals answer for text.
270 pub content: Color32,
271 /// `content-secondary`.
272 ///
273 /// Inactive but usable: it still answers a press. The middle tone of the
274 /// three (wiki `three-tone-convention`), and the one an unchosen option in
275 /// a choice field takes. Added 0.26.0 for that widget, which drew every
276 /// option at full `content` and so said nothing about which one was
277 /// chosen beyond the dot egui paints.
278 ///
279 /// Not [`content_muted`](Self::content_muted), which carries a claim:
280 /// `State::Disabled` resolves to it, so a live control wearing it tells the
281 /// user it will not answer. `makeover-tui` draws the same widget the same
282 /// way from `makeover-tui@230bf63`.
283 ///
284 /// A step of `content` toward the page, derived at load by `makeover`
285 /// rather than authored, so it is read off the resolved theme here like
286 /// any other token and never re-derived.
287 pub content_secondary: Color32,
288 /// `content-muted`.
289 ///
290 /// A field's hint, and what
291 /// [`makeover_layout::State::Disabled`](makeover_layout::State::Disabled)
292 /// resolves to. Both readings come from the description rather than from
293 /// here: `State::Disabled` names this intent by token.
294 pub content_muted: Color32,
295 /// `action-primary`.
296 ///
297 /// What a control is drawn in. Added 0.12.0 with the table renderer, for the
298 /// reason `content` was added 0.5.0 with the field renderer: a link in a
299 /// cell is the first thing here that needs the action intent, and a palette
300 /// should carry what is used.
301 ///
302 /// This is the intent [`CellPart`](makeover_layout::CellPart) exists to
303 /// separate. A cell holding a control took the cell's text colour until the
304 /// description could say otherwise, which is the drift `makeover-layout`
305 /// 0.14.0 named and `makeover-webview` 0.25.0 fixed on its own side.
306 pub action: Color32,
307 /// `danger`.
308 ///
309 /// A field's error message, a destructive control, a bar that has run over.
310 pub danger: Color32,
311 /// `success`.
312 ///
313 /// Added 0.18.0 with [`widget`], which is the first thing here that draws a
314 /// [`Tone`]. The three status intents arrive together and not one at a
315 /// time: [`Tone`] is five members wide and a resolver missing one has to
316 /// invent a colour for it, which is the substitution this crate spent
317 /// 0.2.0 removing from [`Palette::fill`].
318 pub success: Color32,
319 /// `warning`.
320 pub warning: Color32,
321 /// `info`.
322 pub info: Color32,
323 }
324
325 impl Palette {
326 /// Resolve a surface intent, or `None` for one this renderer does not know.
327 ///
328 /// A plain lookup. There is still no substitution: the old one existed only
329 /// while `surface-well` was underived, and every consumer reads the real
330 /// token now.
331 ///
332 /// `Option` since 0.3.0, because [`Fill`] became `#[non_exhaustive]` in
333 /// `makeover-layout` 0.4.0 and a total function over an open enum can only
334 /// stay total by inventing a colour for a member it has never heard of.
335 /// That is the substitution this crate spent 0.2.0 removing, so the return
336 /// type moved instead. Every member the description has today is answered
337 /// with `Some`.
338 #[must_use]
339 pub const fn fill(&self, fill: Fill) -> Option<Color32> {
340 match fill {
341 Fill::Page => Some(self.page),
342 Fill::Raised => Some(self.raised),
343 Fill::Overlay => Some(self.overlay),
344 Fill::Well => Some(self.well),
345 Fill::Sunken => Some(self.sunken),
346 _ => None,
347 }
348 }
349
350 /// The colour a [`Tone`] reads as.
351 ///
352 /// Total, unlike [`fill`](Self::fill), and the difference is not an
353 /// inconsistency. `Fill` is `#[non_exhaustive]` and `Tone` is not: the
354 /// description layer settled tone at five members and grows surfaces, so a
355 /// total function here cannot be made to invent a colour by an upstream
356 /// release the way a total `fill` could.
357 ///
358 /// [`Tone::Neutral`] is [`content`](Self::content) rather than a colour of
359 /// its own, which is what "an ordinary fact" means: a neutral badge is text
360 /// in a box, not a fifth status.
361 #[must_use]
362 pub const fn tone(&self, tone: Tone) -> Color32 {
363 match tone {
364 Tone::Neutral => self.content,
365 Tone::Info => self.info,
366 Tone::Success => self.success,
367 Tone::Warning => self.warning,
368 Tone::Danger => self.danger,
369 }
370 }
371
372 /// The cast shadow for a surface that overlays the page.
373 ///
374 /// What "overlaying" means in immediate mode, answered rather than skipped.
375 /// egui already paints shadows for its menus and windows through
376 /// [`egui::Frame::shadow`], so the honest port is to hand that machinery the
377 /// theme's tone instead of egui's own default, not to invent a painter here
378 /// the way [`paint_bevel`] had to.
379 ///
380 /// The geometry matches what `makeover-webview` composes, in points rather
381 /// than pixels: a small downward offset and a wide soft blur. A Platinum-era
382 /// menu sits just off the page rather than hovering above it.
383 ///
384 /// ```no_run
385 /// # let palette: makeover_immediate::Palette = unimplemented!();
386 /// # let ui: &mut egui::Ui = unimplemented!();
387 /// egui::Frame::popup(ui.style())
388 /// .shadow(palette.cast())
389 /// .show(ui, |ui| { ui.label("over the page"); });
390 /// ```
391 #[must_use]
392 pub const fn cast(&self) -> egui::Shadow {
393 egui::Shadow {
394 offset: [0, 2],
395 blur: 24,
396 spread: 0,
397 color: self.elevation,
398 }
399 }
400
401 /// Resolve a bevel edge intent.
402 #[must_use]
403 pub const fn edge(&self, edge: Edge) -> Color32 {
404 match edge {
405 Edge::Light => self.bevel_light,
406 Edge::Dark => self.bevel_dark,
407 }
408 }
409 }
410
411 /// The geometry a framed region is drawn with.
412 ///
413 /// Every field is a value, which is why they all arrive from the caller:
414 /// radius and border width belong to `makeover-geometry`, and margins come
415 /// from its relational gaps.
416 #[derive(Debug, Clone, Copy, PartialEq)]
417 pub struct FrameStyle {
418 /// Corner radius. Square under the Platinum default.
419 pub radius: CornerRadius,
420 /// Inner margin between the frame and its contents.
421 pub margin: Margin,
422 /// Bevel stroke width, in points.
423 pub stroke: f32,
424 }
425
426 impl Default for FrameStyle {
427 /// A one-point square frame with no inner margin.
428 fn default() -> Self {
429 Self {
430 radius: CornerRadius::ZERO,
431 margin: Margin::ZERO,
432 stroke: 1.0,
433 }
434 }
435 }
436
437 /// Paint a two-tone edge just inside `rect`.
438 ///
439 /// Fill first, bevel after: this adds two polylines and nothing else, so it
440 /// composes over whatever is already there. That is what lets it go over an
441 /// [`egui::TextEdit`] after `ui.add`, where the widget's own fill has landed.
442 ///
443 /// Two three-point polylines meeting at opposite corners, rather than four
444 /// segments, so egui mitres the corner joins instead of leaving a notch.
445 ///
446 /// The dark polyline is drawn second, so the two corners where the runs meet
447 /// take its tone. That is the right answer here rather than a concession.
448 /// [`makeover_layout::Bevel`] holds those corners to belong to both edges, and
449 /// a renderer with room to divide one should; at the default one-point stroke
450 /// the corner is a one-point square, so the division is sub-pixel and
451 /// antialiasing resolves it to the same blend the mitre already gives. Splitting
452 /// it would add a seam and no information. `makeover-tui` does split, because a
453 /// terminal cell is large enough that not splitting costs a visible cell of edge
454 /// weight — the same rule, at a resolution where it has something to say.
455 pub fn paint_bevel(painter: &Painter, rect: Rect, bevel: Bevel, palette: &Palette, stroke: f32) {
456 let (top_left, bottom_right) = bevel.edges();
457
458 // Inset by half a stroke so the line lands inside `rect` rather than
459 // straddling its edge, which on a fractional-scale display is the
460 // difference between one crisp pixel and two dim ones.
461 let r = rect.shrink(stroke / 2.0);
462
463 painter.add(Shape::line(
464 vec![r.left_bottom(), r.left_top(), r.right_top()],
465 Stroke::new(stroke, palette.edge(top_left)),
466 ));
467 painter.add(Shape::line(
468 vec![r.right_top(), r.right_bottom(), r.left_bottom()],
469 Stroke::new(stroke, palette.edge(bottom_right)),
470 ));
471 }
472
473 /// Draw a region at a given [`Depth`]: its fill and its edge, together.
474 ///
475 /// [`Depth::Flat`] gets neither, and inherits whatever it sits on. That is the
476 /// difference between level-with and painted-the-same-colour, and it is the
477 /// reason `Depth::fill` returns an [`Option`] rather than defaulting to the
478 /// page.
479 pub fn frame<R>(
480 ui: &mut Ui,
481 depth: Depth,
482 palette: &Palette,
483 style: FrameStyle,
484 add_contents: impl FnOnce(&mut Ui) -> R,
485 ) -> R {
486 let mut f = egui::Frame::new()
487 .corner_radius(style.radius)
488 .inner_margin(style.margin);
489 // Two ways there is no fill to paint, and they collapse to the same
490 // outcome: the depth names none (Depth::Flat), or it names one this
491 // renderer cannot resolve. Either way the frame goes unfilled and the
492 // bevel below carries the depth on its own, which is the rule this
493 // module already documents for Flat.
494 if let Some(fill) = depth.fill().and_then(|f| palette.fill(f)) {
495 f = f.fill(fill);
496 }
497 // A surface that overlays the page is cast onto it. [`Palette::cast`] has
498 // answered what that means here since 0.10.0 and nothing could reach it: a
499 // description had no way to say Overlay until makeover-layout 0.14.0, so
500 // the answer sat beside the question. Keyed off the fill rather than the
501 // variant, so it stays right for whatever else the description calls an
502 // overlay later.
503 if depth.fill() == Some(Fill::Overlay) {
504 f = f.shadow(palette.cast());
505 }
506 let framed = f.show(ui, add_contents);
507 if let Some(bevel) = depth.bevel() {
508 paint_bevel(
509 ui.painter(),
510 framed.response.rect,
511 bevel,
512 palette,
513 style.stroke,
514 );
515 }
516 framed.inner
517 }
518
519 /// The geometry a field group is drawn with.
520 ///
521 /// Values again, for the reason [`FrameStyle`] is: every number here belongs to
522 /// `makeover-geometry` and arrives already resolved.
523 #[derive(Debug, Clone, Copy, PartialEq)]
524 pub struct FieldStyle {
525 /// The well a text control sits in.
526 pub frame: FrameStyle,
527 /// Between a field's own parts: its label, its control, its hint and its
528 /// error.
529 pub gap: f32,
530 /// Between one field and the next.
531 pub group_gap: f32,
532 /// What marks a required field, appended to its label.
533 ///
534 /// A knob rather than a constant, because it is the one piece of *copy* in
535 /// this crate and copy is not a renderer's call. A webview does not need it
536 /// at all — it emits the `required` attribute and the browser answers — so
537 /// this renderer is the first place where a compulsory field either shows
538 /// that it is or silently does not.
539 pub required_marker: &'static str,
540 }
541
542 impl Default for FieldStyle {
543 /// The default frame, no gaps, and an asterisk.
544 fn default() -> Self {
545 Self {
546 frame: FrameStyle::default(),
547 gap: 0.0,
548 group_gap: 0.0,
549 required_marker: "*",
550 }
551 }
552 }
553
554 /// What the field currently holds, borrowed from wherever the app keeps it.
555 ///
556 /// The immediate-mode counterpart of `makeover_webview::form::Value`, and the
557 /// place the two renderers are forced apart: there the value is read back out
558 /// of the DOM after the fact, and here the widget writes through this borrow as
559 /// it is edited. Same reason the description carries neither.
560 ///
561 /// An enum rather than a bag of options, on the reasoning
562 /// `makeover_webview::form::Value` records: a checkbox holding a string is
563 /// unsayable here, where a struct would let it be said and then have to cope.
564 #[derive(Debug, Default)]
565 pub enum Filling<'a> {
566 /// Nothing to edit. The control is drawn and does not answer.
567 #[default]
568 Absent,
569 /// The buffer behind anything that takes typed text, a select included:
570 /// what a select holds is the `value` of one of its [`Choice`]s.
571 ///
572 /// [`Choice`]: makeover_layout::Choice
573 Text(&'a mut String),
574 /// A checkbox, on or off.
575 On(&'a mut bool),
576 }
577
578 /// The label, marked if the field is compulsory.
579 fn label_text(field: &Field<'_>, style: &FieldStyle) -> String {
580 if field.required {
581 format!("{} {}", field.label, style.required_marker)
582 } else {
583 field.label.to_owned()
584 }
585 }
586
587 /// The four shapes a control comes in here, which is fewer than there are
588 /// kinds.
589 ///
590 /// [`FieldKind`] is `#[non_exhaustive]` and grows; this does not, because the
591 /// ways egui has of asking for a value do not. Reducing the open set to this
592 /// closed one in one total function is what keeps a new kind from needing a new
593 /// arm at every match below.
594 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
595 enum Control {
596 /// Typed into, so it is drawn as a well: the user looks into it.
597 Typed,
598 /// Picked from a control that shows one option at a time. Pressed rather
599 /// than looked into, so egui's own control painting stands.
600 Chosen,
601 /// Picked from options that are all on screen at once.
602 ///
603 /// Apart from [`Chosen`](Self::Chosen) because the description holds them
604 /// apart, and holding them apart is the whole content of
605 /// [`FieldKind::Radio`]: same question, and an answer the user can read
606 /// without opening anything.
607 Listed,
608 /// Held on or off.
609 Toggled,
610 /// Dragged across an extent that is on screen the whole time.
611 ///
612 /// Apart from [`Typed`](Self::Typed) for the reason
613 /// [`FieldKind::Range`] is apart from `Number`: the two ends are what the
614 /// question means, so a well with a figure in it is not a quieter version
615 /// of this control, it is a different one.
616 Slid,
617 }
618
619 /// Which shape a kind takes.
620 ///
621 /// The wildcard falls to [`Control::Typed`] on purpose: a kind added to the
622 /// description since this renderer was built degrades to a text box, which
623 /// accepts any value the others would, rather than to nothing drawn at all.
624 ///
625 /// `FieldKind::File` lands there as of makeover-layout 0.11.0, and it is left
626 /// there rather than grown a shape of its own. egui's honest answer is a button
627 /// that opens a native picker, which is a fifth control and a file-dialog
628 /// dependency; no consumer of this crate asks for a file field yet. Same
629 /// position this crate took on `Meter` at 0.10.0: the membership test is that
630 /// every renderer *could* answer honestly, not that each one does on the day.
631 /// A path in a text box is not nothing, and it is what an app that needs this
632 /// tomorrow gets today.
633 ///
634 /// makeover-layout 0.31.0 added `Field::accept` and `Field::multiple`, and this
635 /// position is what they land on: both are the picker's arguments, and this
636 /// renderer has no picker to give them to. They are not lost — the description
637 /// still carries them, and the day the native dialog arrives here it is opened
638 /// with them rather than with a filter written twice.
639 ///
640 /// `FieldKind::Date` and `FieldKind::DateTime` land there too, as of
641 /// makeover-layout 0.15.0, on the same footing and with one thing owed. A
642 /// calendar is a sixth control and bare `egui` has none, so a typed value is
643 /// the honest answer here; what the app gets is the format the description
644 /// names, `makeover_layout::DATE_FORMAT` and `DATETIME_FORMAT`, which is why
645 /// those are constants rather than a sentence. audiofiles is the only consumer
646 /// of this crate and asks for neither today. A calendar popup is the upgrade
647 /// whenever one does.
648 const fn control_shape(kind: FieldKind) -> Control {
649 match kind {
650 FieldKind::Select => Control::Chosen,
651 FieldKind::Radio => Control::Listed,
652 FieldKind::Checkbox => Control::Toggled,
653 FieldKind::Range => Control::Slid,
654 _ => Control::Typed,
655 }
656 }
657
658 /// The shape the field actually gets, which is the kind's unless the field is
659 /// missing what that shape needs.
660 ///
661 /// One case, and `makeover-layout` names it: a [`FieldKind::Range`] carries its
662 /// extent in [`Field::min`] and [`Field::max`], and a range missing an end has
663 /// nothing to slide across. egui's `Slider` demands a `RangeInclusive`, so
664 /// inventing one would be this renderer picking bounds the app never stated and
665 /// the user then dragging against them.
666 ///
667 /// It falls back to [`Control::Typed`], which is where every kind this renderer
668 /// cannot draw natively already lands: a number in a well is a true report of
669 /// the value and takes any answer the slider would.
670 fn shape_of(field: &Field<'_>) -> Control {
671 match control_shape(field.kind) {
672 Control::Slid if !field.bounded() => Control::Typed,
673 shape => shape,
674 }
675 }
676
677 /// The two ends of a range, as egui wants them.
678 ///
679 /// `None` when either end is missing or is not a number this host can read.
680 /// The description carries the bounds as text on purpose — the bound of a date
681 /// is a date — so parsing them is the renderer's job and failing to is a real
682 /// outcome rather than an assertion.
683 fn extent(field: &Field<'_>) -> Option<RangeInclusive<f64>> {
684 let min = field.min?.parse::<f64>().ok()?;
685 let max = field.max?.parse::<f64>().ok()?;
686 Some(min..=max)
687 }
688
689 /// How many decimals to write a dragged value back with.
690 ///
691 /// Read off [`Field::step`], which is the only thing that says what
692 /// granularity the question has: a step of `0.01` is a two-decimal question and
693 /// a step of `1` is a whole-number one. Without a step the host's own
694 /// granularity stands, and egui's is continuous, so the value is written back
695 /// at whatever precision it round-trips at.
696 fn decimals(step: Option<&str>) -> Option<usize> {
697 let step = step?;
698 Some(match step.split_once('.') {
699 Some((_, fraction)) => fraction.trim_end_matches('0').len(),
700 None => 0,
701 })
702 }
703
704 /// What a select shows for the value it currently holds.
705 ///
706 /// A value no option carries stays on screen as itself rather than reading as
707 /// whichever option happens to be first. goingson saved a backup retention of
708 /// 10 against a 1/3/7/14/0 list and the browser silently showed it as 1, so the
709 /// next save wrote a value nobody chose; `makeover-webview` grew the fix as a
710 /// stray `<option>` and this is the same fix in the shape egui allows.
711 ///
712 /// The empty value is the one case that reads as unanswered rather than as an
713 /// answer, and [`chosen_text`] is what puts the field's ghost text there.
714 fn shown_label<'a>(options: &'a [Choice<'a>], value: &'a str) -> &'a str {
715 options
716 .iter()
717 .find(|opt| opt.value == value)
718 .map_or(value, |opt| opt.label)
719 }
720
721 /// What a select's closed control reads, and in which tone.
722 ///
723 /// A chooser with nothing chosen showed an empty box: `shown_label` falls back
724 /// to the value, and the unanswered value is the empty string. So an app with
725 /// an instruction to give — audiofiles' "Select device..." — had nowhere to put
726 /// it but a disabled button elsewhere on the screen, which is the affordance
727 /// this vocabulary keeps moving messages *off*.
728 ///
729 /// [`Field::placeholder`] is already the description's word for "what the field
730 /// reads while it is empty" and was honoured by the typed kinds alone, so
731 /// nothing new is said here; the renderer is what had not caught up. Muted
732 /// because it is not an answer, the same tone the typed kinds' ghost text takes
733 /// three lines up.
734 ///
735 /// A value no option carries but that is *not* empty stays as itself, in
736 /// `content`: that is the goingson retention bug and it is a wrong answer
737 /// rather than an absent one.
738 ///
739 /// Returns the words and the tone rather than a built [`RichText`], because
740 /// what it decides is both of them and only one of them is readable back off a
741 /// `RichText`.
742 ///
743 /// [`Field::placeholder`]: makeover_layout::Field::placeholder
744 fn chosen_text<'a>(field: &'a Field<'a>, value: &'a str, palette: &Palette) -> (&'a str, Color32) {
745 match field.placeholder {
746 Some(ghost) if value.is_empty() => (ghost, palette.content_muted),
747 _ => (shown_label(field.options, value), palette.content),
748 }
749 }
750
751 /// What one option in a choice field is drawn in.
752 ///
753 /// The chosen one is the emphasised thing and takes `content`; the rest take
754 /// [`content_secondary`](Palette::content_secondary), because an option that is
755 /// not chosen is still an option and pressing it chooses it. Muted would be the
756 /// lie: [`State::Disabled`] resolves to it, so a five-option field read as one
757 /// live row and four dead ones. `makeover-tui` draws it the same way
758 /// (`makeover-tui@230bf63`); wiki `three-tone-convention` is the table.
759 fn option_color(value: &str, option: &str, palette: &Palette) -> Color32 {
760 if value == option {
761 palette.content
762 } else {
763 palette.content_secondary
764 }
765 }
766
767 /// The control alone, without its label, hint or error.
768 fn control(
769 ui: &mut Ui,
770 field: &Field<'_>,
771 filling: Filling<'_>,
772 palette: &Palette,
773 style: &FieldStyle,
774 ) -> Response {
775 // The mismatch path: described as one thing and filled as another. Nothing
776 // here can fix it, so it is drawn as the empty, inert version of what was
777 // described — visible on screen, in the way an empty select is at the
778 // webview renderer, rather than reported in a log nobody reads.
779 let mut discard = String::new();
780 let mut off = false;
781
782 match shape_of(field) {
783 Control::Slid => {
784 let value = match filling {
785 Filling::Text(text) => text,
786 _ => &mut discard,
787 };
788 // `shape_of` has already refused an unbounded range, so the extent
789 // is only missing here if a bound is not a number — a date range,
790 // say, which this control cannot draw either.
791 let Some(extent) = extent(field) else {
792 return ui.label(RichText::new(value.as_str()).color(palette.content));
793 };
794
795 // A value the host cannot read starts at the low end rather than at
796 // zero, which may be outside the extent entirely. Nothing is
797 // written back until the user drags, so an unreadable value the app
798 // put there survives being looked at.
799 let mut number = value.parse::<f64>().unwrap_or(*extent.start());
800 // The granularity is the curve's as of makeover-layout 0.32.0. It
801 // is still in the value's own units, so the display precision is
802 // read off it exactly as before.
803 let step = field.curve.step();
804 let mut slider = Slider::new(&mut number, extent.clone()).text("");
805 if let Some(places) = decimals(step) {
806 slider = slider.max_decimals(places);
807 }
808 if let Some(step) = step.and_then(|s| s.parse::<f64>().ok()) {
809 slider = slider.step_by(step);
810 }
811 // egui's own constant-ratio track, which is this host's answer to
812 // `Curve::Logarithmic`. `is_ratio` rather than a match on the
813 // variant, because a ratio across zero is not one: makeover-layout
814 // decides the fallback so that four renderers cannot disagree about
815 // when it applies.
816 if field.curve.is_ratio(*extent.start(), *extent.end()) {
817 slider = slider.logarithmic(true);
818 }
819 let response = ui.add(slider);
820 if response.changed() {
821 *value = match decimals(step) {
822 Some(places) => format!("{number:.places$}"),
823 None => number.to_string(),
824 };
825 }
826 response
827 }
828 Control::Typed => {
829 let text = match filling {
830 Filling::Text(text) => text,
831 _ => &mut discard,
832 };
833 // An empty frame and no margin: the well is this crate's, and egui's
834 // own control background and padding would sit underneath it saying
835 // something different about both.
836 // Keyed on the description's own `multiline` and not on the
837 // member: a markdown field is several lines by definition, and a
838 // single-line edit would be a control the value cannot fit in. egui
839 // does nothing else with the markdown, which is the honest answer
840 // rather than a gap -- the source is text, and editing it as text
841 // loses none of it.
842 let mut edit = if field.kind.multiline() {
843 TextEdit::multiline(text)
844 } else {
845 TextEdit::singleline(text)
846 }
847 .frame(egui::Frame::NONE)
848 .margin(Margin::ZERO)
849 .text_color(palette.content)
850 .password(field.kind.confidential());
851 if let Some(ghost) = field.placeholder {
852 edit = edit.hint_text(RichText::new(ghost).color(palette.content_muted));
853 }
854 frame(ui, Depth::Well, palette, style.frame, |ui| ui.add(edit))
855 }
856 Control::Toggled => {
857 let on = match filling {
858 Filling::On(on) => on,
859 _ => &mut off,
860 };
861 ui.checkbox(on, RichText::new(field.label).color(palette.content))
862 }
863 Control::Listed => {
864 let value = match filling {
865 Filling::Text(text) => text,
866 _ => &mut discard,
867 };
868 // No `shown_label` counterpart, and none is needed: a value no
869 // option carries leaves every button unfilled, which is already
870 // the honest report on screen. The select needs the fix because it
871 // has one slot and must put *something* in it.
872 let group = ui.vertical(|ui| {
873 let mut answered: Option<Response> = None;
874 for opt in field.options {
875 // An option that cannot be picked yet is drawn and does not
876 // answer, with the precondition beside it rather than
877 // behind a hover: a greyed row with no reason reads as a
878 // dead end, which is the state `Choice::unavailable` exists
879 // to stop being sayable.
880 let picked = if let Some(reason) = opt.unavailable {
881 ui.horizontal(|ui| {
882 let picked = ui
883 .add_enabled_ui(false, |ui| {
884 ui.radio_value(
885 value,
886 opt.value.to_owned(),
887 RichText::new(opt.label).color(palette.content_muted),
888 )
889 })
890 .inner;
891 ui.label(RichText::new(reason).color(palette.content_muted));
892 picked
893 })
894 .inner
895 } else {
896 ui.radio_value(
897 value,
898 opt.value.to_owned(),
899 RichText::new(opt.label).color(option_color(value, opt.value, palette)),
900 )
901 };
902 answered = Some(match answered {
903 Some(prev) => prev.union(picked),
904 None => picked,
905 });
906 }
907 answered
908 });
909 // A group described with no options answers as its own empty area
910 // rather than as no response at all, which keeps the caller's
911 // `.changed()` chain working on a field whose option list has not
912 // loaded yet.
913 group.inner.unwrap_or(group.response)
914 }
915 Control::Chosen => {
916 let value = match filling {
917 Filling::Text(text) => text,
918 _ => &mut discard,
919 };
920 let (shown, tone) = chosen_text(field, value, palette);
921 ComboBox::from_id_salt(field.name)
922 .selected_text(RichText::new(shown).color(tone))
923 .show_ui(ui, |ui| {
924 for opt in field.options {
925 // Same rule as the radio group: shown, inert, and
926 // saying why. A closed control hides its list, so the
927 // reason has to travel with the row it belongs to.
928 if let Some(reason) = opt.unavailable {
929 ui.add_enabled_ui(false, |ui| {
930 ui.selectable_value(
931 value,
932 opt.value.to_owned(),
933 RichText::new(format!("{} {reason}", opt.label))
934 .color(palette.content_muted),
935 );
936 });
937 continue;
938 }
939 ui.selectable_value(
940 value,
941 opt.value.to_owned(),
942 RichText::new(opt.label).color(option_color(value, opt.value, palette)),
943 );
944 }
945 })
946 .response
947 }
948 }
949 }
950
951 /// One field, as the column the app drops into its form.
952 ///
953 /// The anatomy is `makeover-webview`'s, so the two renderers put a form
954 /// together the same way: label, control, hint, error, top to bottom, with a
955 /// checkbox labelling itself instead of taking a label above.
956 ///
957 /// Returns [`None`] for a [`FieldKind::Hidden`] field, which is what
958 /// [`FieldKind::visible`] means and is the honest answer here: a webview still
959 /// emits an input for it because the form submits, and an immediate-mode
960 /// renderer has no form and no submission, so a hidden field is a value the app
961 /// already holds and there is nothing to draw or to respond to.
962 ///
963 /// `state` is the description's interaction axis.
964 /// [`State::Disabled`] greys the field and stops it answering, through
965 /// [`State::suppresses_interaction`] rather than through a second reading of
966 /// what disabled means. Focus is not on that axis and never reaches here: egui
967 /// owns reach, focus and the ring for this renderer, and one ring means not a
968 /// second one per renderer that happens to have opinions.
969 pub fn field(
970 ui: &mut Ui,
971 field: &Field<'_>,
972 filling: Filling<'_>,
973 state: Option<State>,
974 palette: &Palette,
975 style: &FieldStyle,
976 ) -> Option<Response> {
977 if !field.kind.visible() {
978 return None;
979 }
980 let enabled = !state.is_some_and(State::suppresses_interaction);
981 let text = if enabled {
982 palette.content
983 } else {
984 palette.content_muted
985 };
986
987 let response = ui
988 .vertical(|ui| {
989 ui.spacing_mut().item_spacing.y = style.gap;
990
991 // A checkbox labels itself, on the right of the box.
992 // `FieldKind::labels_itself` is the description saying so, and both
993 // webview apps special-cased it inline before it did.
994 if !field.kind.labels_itself() {
995 ui.label(RichText::new(label_text(field, style)).color(text));
996 }
997
998 let response = ui
999 .add_enabled_ui(enabled, |ui| control(ui, field, filling, palette, style))
1000 .inner;
1001
1002 // Standing help first, then what is wrong now. Both, in that order,
1003 // for the reason the webview renderer names both in
1004 // `aria-describedby`: an error appearing must not take the hint
1005 // away with it.
1006 if let Some(hint) = field.hint {
1007 ui.label(RichText::new(hint).color(palette.content_muted));
1008 }
1009 if let Some(error) = field.error {
1010 ui.label(RichText::new(error).color(palette.danger));
1011 }
1012 response
1013 })
1014 .inner;
1015
1016 Some(response)
1017 }
1018
1019 /// A set of fields, laid down a column.
1020 ///
1021 /// `show_extended` is the disclosure, and it is a parameter rather than state
1022 /// held here because the disclosure belongs to the *form* and not to any field:
1023 /// [`Field::extended`] marks which fields are behind one, and the app owns
1024 /// whether it is open. That is the same division `makeover-webview` draws when
1025 /// it marks the group `data-extended` and emits no control to toggle it.
1026 ///
1027 /// `draw` is called once per field that should be visible, in order. Taking a
1028 /// callback rather than a slice of [`Filling`]s is what keeps the app's own
1029 /// values borrowed one at a time: a form's fields usually live in different
1030 /// structs, and a parallel array would have to be built each frame and kept in
1031 /// step with the description by hand.
1032 pub fn group<'a>(
1033 ui: &mut Ui,
1034 fields: &'a [Field<'a>],
1035 show_extended: bool,
1036 style: &FieldStyle,
1037 mut draw: impl FnMut(&mut Ui, &'a Field<'a>),
1038 ) {
1039 ui.vertical(|ui| {
1040 ui.spacing_mut().item_spacing.y = style.group_gap;
1041 for f in fields {
1042 if f.extended && !show_extended {
1043 continue;
1044 }
1045 draw(ui, f);
1046 }
1047 });
1048 }
1049
1050 #[cfg(test)]
1051 mod tests {
1052 use super::*;
1053
1054 fn palette(well: Color32) -> Palette {
1055 Palette {
1056 page: Color32::from_rgb(1, 1, 1),
1057 raised: Color32::from_rgb(2, 2, 2),
1058 overlay: Color32::from_rgb(3, 3, 3),
1059 well,
1060 sunken: Color32::from_rgb(4, 4, 4),
1061 bevel_light: Color32::WHITE,
1062 bevel_dark: Color32::BLACK,
1063 elevation: Color32::from_black_alpha(46),
1064 content: Color32::from_rgb(5, 5, 5),
1065 content_secondary: Color32::from_rgb(55, 55, 55),
1066 content_muted: Color32::from_rgb(6, 6, 6),
1067 action: Color32::from_rgb(7, 7, 7),
1068 danger: Color32::from_rgb(8, 8, 8),
1069 success: Color32::from_rgb(9, 9, 9),
1070 warning: Color32::from_rgb(10, 10, 10),
1071 info: Color32::from_rgb(11, 11, 11),
1072 }
1073 }
1074
1075 /// The cast is egui's own shadow type carrying the theme's tone, which is
1076 /// the whole of what this crate had to decide for it: unlike a bevel, egui
1077 /// already knows how to paint one.
1078 #[test]
1079 fn the_cast_hands_egui_the_themes_tone() {
1080 let p = palette(Color32::from_rgb(9, 9, 9));
1081 let cast = p.cast();
1082 assert_eq!(cast.color, p.elevation);
1083 assert!(cast.blur > 0, "a cast shadow is soft");
1084 assert_eq!(cast.offset, [0, 2], "it falls downward and only a little");
1085 }
1086
1087 #[test]
1088 fn a_well_resolves_to_its_own_token() {
1089 // No substitution left. The page-filled well was a stand-in for a
1090 // token that did not exist yet; it exists now.
1091 let w = Color32::from_rgb(9, 9, 9);
1092 let p = palette(w);
1093 assert_eq!(p.fill(Fill::Well), Some(w));
1094 assert_ne!(p.fill(Fill::Well), Some(p.page));
1095 }
1096
1097 #[test]
1098 fn every_intent_is_a_plain_lookup() {
1099 let p = palette(Color32::from_rgb(9, 9, 9));
1100 assert_eq!(p.fill(Fill::Page), Some(p.page));
1101 assert_eq!(p.fill(Fill::Raised), Some(p.raised));
1102 assert_eq!(p.fill(Fill::Overlay), Some(p.overlay));
1103 }
1104
1105 /// Sunken is its own colour, not the well's and not the page's. The two
1106 /// are authored in opposite directions and an earlier cut of the
1107 /// description conflated them.
1108 #[test]
1109 fn sunken_is_neither_the_well_nor_the_page() {
1110 let p = palette(Color32::from_rgb(9, 9, 9));
1111 assert_eq!(p.fill(Fill::Sunken), Some(p.sunken));
1112 assert_ne!(p.fill(Fill::Sunken), p.fill(Fill::Well));
1113 assert_ne!(p.fill(Fill::Sunken), p.fill(Fill::Page));
1114 }
1115
1116 #[test]
1117 fn a_raised_region_never_resolves_to_the_well_fill() {
1118 // The cross-app bug, asserted at the renderer boundary this time.
1119 let p = palette(Color32::from_rgb(9, 9, 9));
1120 let raised = Depth::Raised.fill().and_then(|f| p.fill(f));
1121 let well = Depth::Well.fill().and_then(|f| p.fill(f));
1122 assert_eq!(raised, Some(p.raised));
1123 assert_ne!(raised, well);
1124 }
1125
1126 #[test]
1127 fn an_overlay_is_cast_onto_the_page_and_takes_no_edge() {
1128 // makeover-layout 0.14.0 is what made this reachable. The answer was
1129 // already here at 0.10.0 and the question could not be asked.
1130 let p = palette(Color32::from_rgb(9, 9, 9));
1131 assert_eq!(
1132 Depth::Overlay.fill().and_then(|f| p.fill(f)),
1133 Some(p.overlay)
1134 );
1135 assert_eq!(Depth::Overlay.bevel(), None);
1136 // The shadow `frame` reaches for is the theme's tone rather than
1137 // egui's default, which is the whole reason `cast` exists.
1138 assert_eq!(p.cast().color, p.elevation);
1139 }
1140
1141 #[test]
1142 fn the_lit_edge_swaps_when_a_card_is_pressed() {
1143 let p = palette(Color32::from_rgb(9, 9, 9));
1144 let (tl, _) = Depth::Raised.bevel().unwrap().edges();
1145 let (ptl, _) = Depth::Raised.pressed().bevel().unwrap().edges();
1146 assert_eq!(p.edge(tl), p.bevel_light);
1147 assert_eq!(p.edge(ptl), p.bevel_dark);
1148 }
1149
1150 #[test]
1151 fn flat_asks_for_neither_fill_nor_edge() {
1152 assert!(Depth::Flat.fill().is_none());
1153 assert!(Depth::Flat.bevel().is_none());
1154 }
1155
1156 #[test]
1157 fn a_select_keeps_a_value_none_of_its_options_carries() {
1158 // The save-the-wrong-thing bug, asserted at the second renderer so it
1159 // is not re-found there. goingson's own numbers.
1160 let options = [
1161 Choice::plain("1"),
1162 Choice::plain("3"),
1163 Choice::plain("7"),
1164 Choice::plain("14"),
1165 ];
1166 assert_eq!(shown_label(&options, "10"), "10");
1167 // And a value that does match reads as its label, not as itself.
1168 let spelled = [Choice::new("7", "One week")];
1169 assert_eq!(shown_label(&spelled, "7"), "One week");
1170 }
1171
1172 #[test]
1173 fn an_unanswered_chooser_reads_its_ghost_text_and_reads_it_muted() {
1174 let p = palette(Color32::from_rgb(9, 9, 9));
1175 let options = [Choice::new("sp404", "SP-404")];
1176 let field = Field {
1177 placeholder: Some("Select device..."),
1178 ..Field::select("device", "Conform for device", &options)
1179 };
1180
1181 assert_eq!(
1182 chosen_text(&field, "", &p),
1183 ("Select device...", p.content_muted),
1184 "ghost text is not an answer, so it takes the tone the typed kinds' ghost text does"
1185 );
1186
1187 // Answered, and it is the label that reads rather than the value.
1188 assert_eq!(chosen_text(&field, "sp404", &p), ("SP-404", p.content));
1189 }
1190
1191 #[test]
1192 fn a_wrong_answer_is_not_an_absent_one() {
1193 // The retention-10 bug and the ghost text meet here: a value no option
1194 // carries still reads as itself, because the field IS answered and the
1195 // answer is wrong. Only the empty value is unanswered.
1196 let p = palette(Color32::from_rgb(9, 9, 9));
1197 let options = [Choice::plain("1"), Choice::plain("7")];
1198 let field = Field {
1199 placeholder: Some("Pick one"),
1200 ..Field::select("retention", "Keep backups for", &options)
1201 };
1202
1203 assert_eq!(chosen_text(&field, "10", &p), ("10", p.content));
1204 }
1205
1206 #[test]
1207 fn a_chooser_with_no_ghost_text_is_unchanged() {
1208 // The whole change is opt-in from the description. A field that says
1209 // nothing about its empty state still shows an empty box.
1210 let p = palette(Color32::from_rgb(9, 9, 9));
1211 let options = [Choice::plain("1")];
1212 let field = Field::select("retention", "Keep backups for", &options);
1213 assert_eq!(chosen_text(&field, "", &p), ("", p.content));
1214 }
1215
1216 #[test]
1217 fn a_range_is_slid_and_a_number_is_typed_into() {
1218 // The distinction the kind was added for, at the renderer that has to
1219 // act on it. A well with a figure in it is not a quiet slider.
1220 assert_eq!(control_shape(FieldKind::Range), Control::Slid);
1221 assert_eq!(control_shape(FieldKind::Number), Control::Typed);
1222 }
1223
1224 #[test]
1225 fn a_range_missing_an_end_falls_back_to_a_well() {
1226 // egui's `Slider` demands both ends, so inventing one would be this
1227 // renderer picking bounds the app never stated and the user then
1228 // dragging against them. A typed number takes every answer the slider
1229 // would.
1230 let whole = Field::range("review", "Review above", "0", "1");
1231 assert_eq!(shape_of(&whole), Control::Slid);
1232
1233 let half = Field {
1234 max: Some("1"),
1235 ..Field::new(FieldKind::Range, "review", "Review above")
1236 };
1237 assert_eq!(shape_of(&half), Control::Typed);
1238 assert_eq!(extent(&half), None);
1239
1240 // A bound this host cannot read is the same outcome by a different
1241 // route: the description carries bounds as text because the bound of a
1242 // date is a date.
1243 let dated = Field::range("when", "When", "2026-08-01", "2026-08-31");
1244 assert_eq!(extent(&dated), None);
1245 }
1246
1247 #[test]
1248 fn the_step_decides_how_a_dragged_value_is_written_back() {
1249 // Without it a 0-to-1 threshold writes back whatever float the drag
1250 // landed on, which is the host's granularity and is what the
1251 // description says an absent step means.
1252 assert_eq!(decimals(None), None);
1253 assert_eq!(decimals(Some("1")), Some(0));
1254 assert_eq!(decimals(Some("0.01")), Some(2));
1255 // Trailing zeros are not precision: 0.10 is a one-decimal question.
1256 assert_eq!(decimals(Some("0.10")), Some(1));
1257 }
1258
1259 #[test]
1260 fn an_unavailable_option_is_drawn_muted_rather_than_dropped() {
1261 // The tone rule, at the one place it is a claim rather than a
1262 // preference: this option genuinely will not answer, so muted is the
1263 // truth. The available ones beside it keep the secondary intent.
1264 let p = palette(Color32::from_rgb(9, 9, 9));
1265 let options = [
1266 Choice::new("chromatic", "Chromatic"),
1267 Choice::new("multi", "Multi-sample").unless("Drop a second sample."),
1268 ];
1269 assert!(options[0].available());
1270 assert!(!options[1].available());
1271 assert_eq!(
1272 option_color("chromatic", options[0].value, &p),
1273 p.content,
1274 "the chosen option is the emphasised thing"
1275 );
1276 assert_eq!(
1277 option_color("chromatic", options[1].value, &p),
1278 p.content_secondary,
1279 "and `option_color` never mutes: the unavailable path is what does"
1280 );
1281 }
1282
1283 #[test]
1284 fn only_a_required_field_is_marked() {
1285 let style = FieldStyle::default();
1286 let plain = Field::new(FieldKind::Text, "title", "Title");
1287 assert_eq!(label_text(&plain, &style), "Title");
1288
1289 let required = Field {
1290 required: true,
1291 ..plain
1292 };
1293 assert_eq!(label_text(&required, &style), "Title *");
1294
1295 // The marker is copy and the app owns it, which is why it is a knob.
1296 let house = FieldStyle {
1297 required_marker: "(required)",
1298 ..style
1299 };
1300 assert_eq!(label_text(&required, &house), "Title (required)");
1301 }
1302
1303 #[test]
1304 fn a_select_and_a_checkbox_are_pressed_and_everything_else_is_typed_into() {
1305 // What decides whether the control gets a well. A well is for what the
1306 // user looks into, and only one of these is.
1307 assert_eq!(control_shape(FieldKind::Select), Control::Chosen);
1308 assert_eq!(control_shape(FieldKind::Radio), Control::Listed);
1309 assert_eq!(control_shape(FieldKind::Checkbox), Control::Toggled);
1310 for k in [
1311 FieldKind::Text,
1312 FieldKind::Secret,
1313 FieldKind::Number,
1314 FieldKind::Email,
1315 FieldKind::Url,
1316 FieldKind::Tel,
1317 FieldKind::Textarea,
1318 FieldKind::Rich,
1319 ] {
1320 assert_eq!(control_shape(k), Control::Typed, "{k:?} is typed into");
1321 }
1322 // And the two multi-line ones get a multi-line edit, which is the half
1323 // `control_shape` alone does not say: both are typed into, and only one
1324 // of the two edit shapes can hold a markdown document.
1325 assert!(FieldKind::Rich.multiline());
1326 assert!(FieldKind::Textarea.multiline());
1327 assert!(!FieldKind::Text.multiline());
1328 }
1329
1330 #[test]
1331 fn the_two_option_taking_kinds_are_drawn_differently_on_purpose() {
1332 // The description holds Select and Radio apart, and a renderer that
1333 // collapsed them would silently answer a question the app did not ask:
1334 // audiofiles' storage style is irreversible and its alternatives have
1335 // to be readable without opening anything. Asserting the two shapes
1336 // differ is asserting that distinction survives the trip.
1337 assert!(FieldKind::Select.offers_options());
1338 assert!(FieldKind::Radio.offers_options());
1339 assert_ne!(
1340 control_shape(FieldKind::Select),
1341 control_shape(FieldKind::Radio)
1342 );
1343 }
1344
1345 #[test]
1346 fn an_unchosen_option_is_secondary_and_never_muted() {
1347 let p = palette(Color32::from_rgb(4, 4, 4));
1348 assert_eq!(option_color("wav", "wav", &p), p.content);
1349 assert_eq!(option_color("wav", "aiff", &p), p.content_secondary);
1350 // The whole point of the distinction: muted is what Disabled resolves
1351 // to, so an option wearing it would claim it does not answer a press.
1352 assert_ne!(option_color("wav", "aiff", &p), p.content_muted);
1353 }
1354
1355 #[test]
1356 fn a_hidden_field_draws_nothing_and_answers_nothing() {
1357 // Where the two renderers legitimately part: a webview still emits an
1358 // input because the form submits, and there is no form here.
1359 let f = Field::new(FieldKind::Hidden, "id", "Id");
1360 let p = palette(Color32::from_rgb(9, 9, 9));
1361 egui::__run_test_ui(|ui| {
1362 let drawn = field(ui, &f, Filling::Absent, None, &p, &FieldStyle::default());
1363 assert!(drawn.is_none());
1364 });
1365 }
1366
1367 #[test]
1368 fn a_disabled_field_stops_answering_and_an_unstated_one_does_not() {
1369 let f = Field::new(FieldKind::Text, "title", "Title");
1370 let p = palette(Color32::from_rgb(9, 9, 9));
1371 let style = FieldStyle::default();
1372 egui::__run_test_ui(|ui| {
1373 let mut text = String::from("x");
1374 let disabled = field(
1375 ui,
1376 &f,
1377 Filling::Text(&mut text),
1378 Some(State::Disabled),
1379 &p,
1380 &style,
1381 )
1382 .unwrap();
1383 assert!(!disabled.enabled());
1384
1385 // Stating no state is the ordinary case and answers. Focus used to
1386 // be the counter-example here; it is egui's now and a description
1387 // cannot state it at all.
1388 let mut text = String::from("x");
1389 let plain = field(ui, &f, Filling::Text(&mut text), None, &p, &style).unwrap();
1390 assert!(plain.enabled(), "an unstated field still answers");
1391 });
1392 }
1393
1394 #[test]
1395 fn a_field_described_one_way_and_filled_another_is_drawn_inert() {
1396 // No panic and no write-through. A checkbox handed a string cannot be
1397 // filled, so it is drawn off and left alone.
1398 let f = Field::new(FieldKind::Checkbox, "done", "Done");
1399 let p = palette(Color32::from_rgb(9, 9, 9));
1400 let mut text = String::from("untouched");
1401 egui::__run_test_ui(|ui| {
1402 let drawn = field(
1403 ui,
1404 &f,
1405 Filling::Text(&mut text),
1406 None,
1407 &p,
1408 &FieldStyle::default(),
1409 );
1410 assert!(drawn.is_some());
1411 });
1412 assert_eq!(text, "untouched");
1413 }
1414
1415 #[test]
1416 fn the_disclosure_belongs_to_the_form_and_not_to_the_field() {
1417 let fields = [
1418 Field::new(FieldKind::Text, "title", "Title"),
1419 Field {
1420 extended: true,
1421 ..Field::new(FieldKind::Text, "notes", "Notes")
1422 },
1423 ];
1424 let style = FieldStyle::default();
1425
1426 let mut closed = Vec::new();
1427 egui::__run_test_ui(|ui| {
1428 group(ui, &fields, false, &style, |_, f| closed.push(f.name));
1429 });
1430 assert_eq!(closed, ["title"]);
1431
1432 let mut open = Vec::new();
1433 egui::__run_test_ui(|ui| {
1434 group(ui, &fields, true, &style, |_, f| open.push(f.name));
1435 });
1436 assert_eq!(open, ["title", "notes"]);
1437 }
1438
1439 #[test]
1440 fn the_default_frame_is_square_and_one_point() {
1441 let d = FrameStyle::default();
1442 assert_eq!(d.radius, CornerRadius::ZERO);
1443 assert_eq!(d.margin, Margin::ZERO);
1444 assert!((d.stroke - 1.0).abs() < f32::EPSILON);
1445 }
1446 }
1447