Add interactive_container demo

crates/egui_demo_lib/src/demo/demo_app_windows.rs

@@ -31,6 +31,7 @@ impl Default for Demos {
             Box::<super::font_book::FontBook>::default(),
             Box::<super::frame_demo::FrameDemo>::default(),
             Box::<super::highlighting::Highlighting>::default(),
+            Box::<super::interactive_container::InteractiveContainerDemo>::default(),
             Box::<super::MiscDemoWindow>::default(),
             Box::<super::multi_touch::MultiTouch>::default(),
             Box::<super::painting::Painting>::default(),

crates/egui_demo_lib/src/demo/interactive_container.rs

@@ -0,0 +1,81 @@
+use egui::{Frame, Label, RichText, Sense, UiBuilder, Widget};
+
+/// Showcase [`egui::Ui::read_response`].
+#[derive(PartialEq, Eq, Default)]
+#[cfg_attr(feature = "serde", derive(serde::Deserialize, serde::Serialize))]
+#[cfg_attr(feature = "serde", serde(default))]
+pub struct InteractiveContainerDemo {
+    count: usize,
+}
+
+impl crate::Demo for InteractiveContainerDemo {
+    fn name(&self) -> &'static str {
+        "\u{20E3}TextEdit"
+    }
+
+    fn show(&mut self, ctx: &egui::Context, open: &mut bool) {
+        egui::Window::new(self.name())
+            .open(open)
+            .resizable(false)
+            .show(ctx, |ui| {
+                use crate::View as _;
+                self.ui(ui);
+            });
+    }
+}
+
+impl crate::View for InteractiveContainerDemo {
+    fn ui(&mut self, ui: &mut egui::Ui) {
+        ui.vertical_centered(|ui| {
+            ui.add(crate::egui_github_link_file!());
+        });
+
+        ui.label("This demo showcases how to use Ui::read_response to create interactive container widgets that may contain other widgets.");
+
+        let response = ui
+            .scope_builder(
+                UiBuilder::new()
+                    .id_salt("interactive_container")
+                    .sense(Sense::click()),
+                |ui| {
+                    let response = ui.read_response();
+                    let visuals = ui.style().interact(&response);
+                    let text_color = visuals.text_color();
+
+                    Frame::canvas(ui.style())
+                        .fill(visuals.bg_fill.gamma_multiply(0.3))
+                        .stroke(visuals.bg_stroke)
+                        .inner_margin(ui.spacing().menu_margin)
+                        .show(ui, |ui| {
+                            ui.set_width(ui.available_width());
+
+                            ui.add_space(32.0);
+                            ui.vertical_centered(|ui| {
+                                Label::new(
+                                    RichText::new(format!("{}", self.count))
+                                        .color(text_color)
+                                        .size(32.0),
+                                )
+                                .selectable(false)
+                                .ui(ui);
+                            });
+                            ui.add_space(32.0);
+
+                            ui.horizontal(|ui| {
+                                if ui.button("Reset").clicked() {
+                                    self.count = 0;
+                                }
+                                if ui.button("+ 100").clicked() {
+                                    self.count += 100;
+                                }
+                            });
+                        });
+                },
+            )
+            .response;
+
+        if response.clicked() {
+            self.count += 1;
+        }
+    }
+}

crates/egui_demo_lib/src/demo/mod.rs

@@ -15,6 +15,7 @@ pub mod extra_viewport;
 pub mod font_book;
 pub mod frame_demo;
 pub mod highlighting;
+pub mod interactive_container;
 pub mod misc_demo_window;
 pub mod multi_touch;
 pub mod paint_bezier;