feat(combobox): implement text wrap for selected text (#2272)

* feat(combobox): implement text wrap for selected text

* chore(changelog): add line to changelog

* feat(combobox-text-wrap): make wrap boolean

- specifying a wrap width didn't really make sense so now it's boolean
- the selected text will now use the maximum available width while still
  respecting the spacing and icon coming after it

* feat(combobox-text-wrap): update changelog

CHANGELOG.md

@@ -18,6 +18,7 @@ NOTE: [`epaint`](crates/epaint/CHANGELOG.md), [`eframe`](crates/eframe/CHANGELOG
 * Added `egui::gui_zoom` module with helpers for scaling the whole GUI of an app ([#2239](https://github.com/emilk/egui/pull/2239)).
 * You can now put one interactive widget on top of another, and only one will get interaction at a time ([#2244](https://github.com/emilk/egui/pull/2244)).
 * Added `ui.centered`.
+* Added possibility to enable text wrap for the selected text of `egui::ComboBox` ([#2272](https://github.com/emilk/egui/pull/2244))
 * Added `Area::constrain` and `Window::constrain` which constrains area to the screen bounds. ([#2270](https://github.com/emilk/egui/pull/2270)).
 * Added `Area::pivot` and `Window::pivot` which controls what part of the window to position. ([#2303](https://github.com/emilk/egui/pull/2303)).
 

crates/egui/src/containers/combo_box.rs

@@ -36,6 +36,7 @@ pub struct ComboBox {
     selected_text: WidgetText,
     width: Option<f32>,
     icon: Option<IconPainter>,
+    wrap_enabled: bool,
 }
 
 impl ComboBox {
@@ -47,6 +48,7 @@ impl ComboBox {
             selected_text: Default::default(),
             width: None,
             icon: None,
+            wrap_enabled: false,
         }
     }
 
@@ -59,6 +61,7 @@ impl ComboBox {
             selected_text: Default::default(),
             width: None,
             icon: None,
+            wrap_enabled: false,
         }
     }
 
@@ -70,6 +73,7 @@ impl ComboBox {
             selected_text: Default::default(),
             width: None,
             icon: None,
+            wrap_enabled: false,
         }
     }
 
@@ -124,6 +128,12 @@ impl ComboBox {
         self
     }
 
+    /// Controls whether text wrap is used for the selected text
+    pub fn wrap(mut self, wrap: bool) -> Self {
+        self.wrap_enabled = wrap;
+        self
+    }
+
     /// Show the combo box, with the given ui code for the menu contents.
     ///
     /// Returns `InnerResponse { inner: None }` if the combo box is closed.
@@ -146,6 +156,7 @@ impl ComboBox {
             selected_text,
             width,
             icon,
+            wrap_enabled,
         } = self;
 
         let button_id = ui.make_persistent_id(id_source);
@@ -154,7 +165,14 @@ impl ComboBox {
             if let Some(width) = width {
                 ui.spacing_mut().slider_width = width; // yes, this is ugly. Will remove later.
             }
-            let mut ir = combo_box_dyn(ui, button_id, selected_text, menu_contents, icon);
+            let mut ir = combo_box_dyn(
+                ui,
+                button_id,
+                selected_text,
+                menu_contents,
+                icon,
+                wrap_enabled,
+            );
             if let Some(label) = label {
                 ir.response
                     .widget_info(|| WidgetInfo::labeled(WidgetType::ComboBox, label.text()));
@@ -221,6 +239,7 @@ fn combo_box_dyn<'c, R>(
     selected_text: WidgetText,
     menu_contents: Box<dyn FnOnce(&mut Ui) -> R + 'c>,
     icon: Option<IconPainter>,
+    wrap_enabled: bool,
 ) -> InnerResponse<Option<R>> {
     let popup_id = button_id.with("popup");
 
@@ -244,10 +263,16 @@ fn combo_box_dyn<'c, R>(
 
     let button_response = button_frame(ui, button_id, is_popup_open, Sense::click(), |ui| {
         // We don't want to change width when user selects something new
-        let full_minimum_width = ui.spacing().slider_width;
+        let full_minimum_width = wrap_enabled
+            .then(|| ui.available_width() - ui.spacing().item_spacing.x * 2.0)
+            .unwrap_or_else(|| ui.spacing().slider_width);
         let icon_size = Vec2::splat(ui.spacing().icon_width);
+        let wrap_width = wrap_enabled
+            .then(|| ui.available_width() - ui.spacing().item_spacing.x - icon_size.x)
+            .unwrap_or(f32::INFINITY);
 
-        let galley = selected_text.into_galley(ui, Some(false), f32::INFINITY, TextStyle::Button);
+        let galley =
+            selected_text.into_galley(ui, Some(wrap_enabled), wrap_width, TextStyle::Button);
 
         let width = galley.size().x + ui.spacing().item_spacing.x + icon_size.x;
         let width = width.at_least(full_minimum_width);