Fix #322: type an exact value into a slider

Click the value next to a slider's name to edit it: the old value starts
selected, Return or clicking away applies the typed number on the
control's steps and range as one undo step (like a keyboard nudge), and
Esc or text that isn't a number keeps the old value. A decimal comma,
a leading + and a % or K unit are accepted. The keys typed go to the
field, not to the shortcuts.

Co-Authored-By: Claude Opus 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_01912WaK6Rmew3wxZuPyX7E8

crates/ui-egui/src/headless.rs

@@ -1053,6 +1053,37 @@ mod tests {
         assert_ne!(h.app.session.active(), Some(first), "advanced");
     }
 
+    /// Click a slider's value and type one (issue #322): Return sets it as one undo step, Esc
+    /// keeps the old value, and the keys typed don't reach the shortcuts (1 = one star).
+    #[test]
+    fn slider_values_can_be_typed() {
+        let mut h = demo([1300.0, 900.0]);
+        let t = Duration::from_secs(10);
+        h.request("ui.set", json!({"view": "detail", "right": "edit"}), t);
+        h.settle(SETTLE);
+        let active = h.app.session.active().unwrap();
+        let exposure = |h: &Headless| h.app.session.develop_of(h.app.session.active().unwrap()).unwrap().light.exposure;
+        let rating = |h: &Headless| h.app.session.catalog.photo(active).unwrap().rating;
+        let (undo0, rating0) = (h.app.session.undo.len(), rating(&h));
+        assert_eq!(h.request("ui.clickWidget", json!({"id": "sliderValue:light.exposure"}), t)["ok"], true);
+        h.request("ui.text", json!({"text": "1,5"}), t);
+        h.request("ui.key", json!({"key": "Enter"}), t);
+        assert!((exposure(&h) - 1.5).abs() < 1e-9, "{}", exposure(&h));
+        assert_eq!(h.app.session.undo.len(), undo0 + 1, "one undo step");
+        assert_eq!(rating(&h), rating0, "typing 1 set no rating");
+        // Esc keeps the value
+        assert_eq!(h.request("ui.clickWidget", json!({"id": "sliderValue:light.exposure"}), t)["ok"], true);
+        h.request("ui.text", json!({"text": "-2"}), t);
+        h.request("ui.key", json!({"key": "Escape"}), t);
+        assert!((exposure(&h) - 1.5).abs() < 1e-9, "{}", exposure(&h));
+        // something that isn't a number changes nothing
+        assert_eq!(h.request("ui.clickWidget", json!({"id": "sliderValue:light.exposure"}), t)["ok"], true);
+        h.request("ui.text", json!({"text": "bright"}), t);
+        h.request("ui.key", json!({"key": "Enter"}), t);
+        assert!((exposure(&h) - 1.5).abs() < 1e-9, "{}", exposure(&h));
+        assert_eq!(h.app.session.undo.len(), undo0 + 1);
+    }
+
     /// Return commits a tool panel back to Edit; elsewhere it does nothing.
     #[test]
     fn return_commits_the_crop_tool() {

crates/ui-egui/src/widgets.rs

@@ -142,8 +142,26 @@ pub struct SliderOut {
     pub reset: bool,
 }
 
+/// What a value typed into a slider asks for (issue #322): a number such as `0.5`, `+12`, `-1,5`
+/// (comma or point) or `5600 K`, on the control's steps and clamped to its range. `None` when it
+/// isn't a finite number, so the slider keeps its value.
+pub fn typed_value(spec: &ControlSpec, text: &str) -> Option<f64> {
+    let t = text.trim().replace(',', ".");
+    let t = t.trim_end_matches(|c: char| c == '%' || c == 'K' || c == 'k' || c.is_whitespace());
+    let v: f64 = t.parse().ok().filter(|v: &f64| v.is_finite())?;
+    let step = spec.step.max(1e-9);
+    Some(((v / step).round() * step).clamp(spec.min, spec.max))
+}
+
+/// A slider's value as shown next to its label.
+fn shown_value(spec: &ControlSpec, v: f64) -> String {
+    let shown = if spec.id == "wb.temp" { format!("{v:.0}") } else { spec.format(v).replace("+0.00", "0").replace("-0.00", "0") };
+    if shown == "+0" || shown == "-0" { "0".to_string() } else { shown }
+}
+
 /// A Lightroom slider row (label + value above a track with a hollow ring thumb).
-/// Double-click the label or thumb to reset. Shift-drag = fine adjustment.
+/// Double-click the label or thumb to reset. Shift-drag = fine adjustment. Click the value to
+/// type one: Return or clicking away applies it, Esc keeps the old one.
 pub fn slider(ui: &mut Ui, spec: &ControlSpec, value: f64, enabled: bool, label_override: Option<&str>) -> SliderOut {
     let t = Tokens::get(ui.ctx());
     let w = ui.available_width();
@@ -159,12 +177,53 @@ pub fn slider(ui: &mut Ui, spec: &ControlSpec, value: f64, enabled: bool, label_
     resp.widget_info(|| egui::WidgetInfo::slider(enabled, value, label_text.clone()));
     let label_resp = ui.interact(label_rect, id.with("label"), Sense::click());
     register(ui.ctx(), format!("slider:{}", spec.id), track_rect);
+    // the value: click it to type an exact one (over the label, so it takes the click)
+    let value_rect = Rect::from_min_max(pos2(label_rect.right() - 64.0, label_rect.top()), label_rect.max);
+    let value_resp = ui.interact(value_rect, id.with("value"), if enabled { Sense::click() } else { Sense::hover() });
+    register(ui.ctx(), format!("sliderValue:{}", spec.id), value_rect);
+    let typing_id = id.with("typing");
+    let field_id = id.with("typingField");
+    let mut typing: Option<String> = ui.data(|m| m.get_temp(typing_id));
+    if enabled && typing.is_none() && value_resp.clicked() {
+        let text = shown_value(spec, value).trim_start_matches('+').to_string();
+        // the old value starts selected, so typing replaces it
+        let mut state = egui::text_edit::TextEditState::load(ui.ctx(), field_id).unwrap_or_default();
+        let all = egui::text::CCursorRange::two(egui::text::CCursor::new(0), egui::text::CCursor::new(text.chars().count()));
+        state.cursor.set_char_range(Some(all));
+        state.store(ui.ctx(), field_id);
+        typing = Some(text);
+        ui.memory_mut(|m| m.request_focus(field_id));
+    }
     let mut out = SliderOut::default();
     let span = (spec.max - spec.min).max(1e-9);
     let to_x = |v: f64| track_rect.left() + ((v - spec.min) / span).clamp(0.0, 1.0) as f32 * track_rect.width();
     let from_x = |x: f32| spec.min + ((x - track_rect.left()) / track_rect.width()).clamp(0.0, 1.0) as f64 * span;
     let mut v = value;
-    if resp.double_clicked() || label_resp.double_clicked() {
+    if let Some(mut text) = typing.take() {
+        let field = egui::TextEdit::singleline(&mut text)
+            .id(field_id)
+            .font(t.font(12.5))
+            .horizontal_align(egui::Align::RIGHT)
+            .desired_width(value_rect.width())
+            .margin(egui::Margin::ZERO);
+        let te = ui.put(value_rect, field);
+        if te.lost_focus() || !enabled {
+            // Esc (or the slider turning off) keeps the old value; Return or clicking away applies
+            let cancelled = !enabled || ui.input(|i| i.key_pressed(egui::Key::Escape));
+            if let Some(nv) = typed_value(spec, &text).filter(|_| !cancelled) {
+                if (nv - value).abs() > 1e-12 {
+                    out.value = Some(nv);
+                    out.drag_started = true;
+                    out.drag_stopped = true;
+                    v = nv;
+                }
+            }
+            ui.data_mut(|m| m.remove::<String>(typing_id));
+        } else {
+            typing = Some(text.clone());
+            ui.data_mut(|m| m.insert_temp(typing_id, text));
+        }
+    } else if resp.double_clicked() || label_resp.double_clicked() {
         out.reset = true;
         out.value = Some(spec.default);
         v = spec.default;
@@ -202,7 +261,7 @@ pub fn slider(ui: &mut Ui, spec: &ControlSpec, value: f64, enabled: bool, label_
             out.drag_stopped = true;
         }
         // ↑ / ↓ while the pointer rests on the row nudge the value (⇧: five times as much)
-        if enabled && out.value.is_none() && ui.rect_contains_pointer(row) {
+        if enabled && out.value.is_none() && typing.is_none() && ui.rect_contains_pointer(row) {
             let (up, down, shift) = ui.input_mut(|i| {
                 let shift = i.modifiers.shift;
                 let m = if shift { egui::Modifiers::SHIFT } else { egui::Modifiers::NONE };
@@ -224,9 +283,12 @@ pub fn slider(ui: &mut Ui, spec: &ControlSpec, value: f64, enabled: bool, label_
     let text_c = if enabled { t.text_label } else { t.text_disabled };
     let p = ui.painter();
     p.text(label_rect.left_center(), Align2::LEFT_CENTER, crate::i18n::tr(label_override.unwrap_or(spec.label)), t.font(12.5), text_c);
-    let shown = if spec.id == "wb.temp" { format!("{v:.0}") } else { spec.format(v).replace("+0.00", "0").replace("-0.00", "0") };
-    let shown = if shown == "+0" || shown == "-0" { "0".to_string() } else { shown };
-    p.text(label_rect.right_center(), Align2::RIGHT_CENTER, shown, t.font(12.5), text_c);
+    if typing.is_none() {
+        p.text(label_rect.right_center(), Align2::RIGHT_CENTER, shown_value(spec, v), t.font(12.5), text_c);
+        if enabled && value_resp.hovered() {
+            ui.ctx().set_cursor_icon(egui::CursorIcon::Text);
+        }
+    }
     let ring = 7.0;
     let tx = to_x(v);
     paint_track(ui, track_rect, &spec.track, &t, tx, ring);
@@ -468,6 +530,23 @@ mod tests {
         assert_eq!(nudged(&spec("wb.temp", 2000.0, 50000.0, 1.0), 6500.0, 1.0), 6550.0);
         assert_eq!(nudged(&spec("light.contrast", -100.0, 100.0, 1.0), 99.0, 5.0), 100.0, "clamped");
     }
+
+    /// Typed values (issue #322): signs, a decimal comma, units; on the control's steps, in range.
+    #[test]
+    fn typed_values_are_stepped_and_clamped() {
+        let exposure = lightcraft_develop::controls::find("light.exposure").unwrap();
+        let contrast = lightcraft_develop::controls::find("light.contrast").unwrap();
+        let temp = lightcraft_develop::controls::find("wb.temp").unwrap();
+        assert_eq!(typed_value(exposure, "1.5"), Some(1.5));
+        assert_eq!(typed_value(exposure, " +0,25 "), Some(0.25));
+        assert_eq!(typed_value(exposure, "-12"), Some(exposure.min), "clamped");
+        assert_eq!(typed_value(contrast, "33.4"), Some(33.0), "on the control's steps");
+        assert_eq!(typed_value(contrast, "-20 %"), Some(-20.0));
+        assert_eq!(typed_value(temp, "5600 K"), Some(5600.0));
+        for bad in ["", "abc", "1.2.3", "NaN", "inf", "--1"] {
+            assert_eq!(typed_value(contrast, bad), None, "{bad:?}");
+        }
+    }
 }
 
 #[cfg(test)]

docs/parity.md

@@ -694,6 +694,7 @@ From `06-shortcuts.md` part 1. Evidence is our binding; conflicts are explained
 | KEY-STRAIGHTEN | Straighten while held — ⌘ drag | P1 | ✅ | `cmd:crop.straighten`, `crates/ui-egui/src/panels/detail.rs` (`straighten_overlay`) | ⌘-drag in Crop draws a level line; the crop tool stays active |
 | KEY-SLIDER-RESET | Reset slider — double-click | P0 | ✅ | `crates/ui-egui/src/widgets.rs` | |
 | KEY-SLIDER-NUDGE | Nudge slider — ↑/↓ | P1 | ✅ | `crates/ui-egui/src/widgets.rs` (`nudged`), `cmd:develop.adjust` | ↑/↓ over any slider: ≈ 1/200 of its range (exposure 0.05, most sliders 1, temperature 50 K); ⇧ ×5; one undo step each |
+| KEY-SLIDER-TYPE | Type a slider value | P1 | ✅ | `crates/ui-egui/src/widgets.rs` (`typed_value`) | click the value next to any slider's name and type one (`1.5`, `+0,25`, `-20`, `5600 K`): Return or clicking away applies it on the control's steps and range as one undo step, Esc keeps the old value; issue #322 |
 | KEY-SHORTCUTS | Shortcut list — ⌘/ | P1 | ✅ | `cmd:app.shortcuts` | |
 | KEY-HELP | Help — F1 | P2 | ✅ | `cmd:app.help` | |
 | KEY-VIDEO-PLAY | Play/pause video — Space | P1 | ⬜ | | |

docs/whats-new.md

@@ -13,6 +13,10 @@
   with a counterpart here come along, the rest is listed.
 - 23 new built-in presets: Portrait, Landscape, Urban, Food, Seasons, Vintage and B&W toners.
 
+### Editing
+- Type an exact value into any slider (issue #322): click the number next to its name, type (`1.5`, `-20`, `5600`)
+  and press Return; Esc keeps the old value.
+
 ### Reliability
 - LightCraft no longer crashes at launch on Windows PCs whose Vulkan driver is broken (issue #136, e.g. some Intel UHD
   630 drivers): on Windows the window and GPU rendering use DirectX 12 only and never load the Vulkan driver unless