Merge branch 'more-plot-items' into line-styles

/ · Jun 14, 2021 · 2c9ac6c · 2c9ac6c
2 parents e5b22a4 + 79a08ac
commit 2c9ac6c
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Showing 2 changed files with 34 additions and 6 deletions.
diff --git a/egui/src/widgets/plot/legend.rs b/egui/src/widgets/plot/legend.rs
@@ -33,24 +33,34 @@ impl Corner {
 #[derive(Clone, Copy, PartialEq)]
 pub struct Legend {
     pub text_style: TextStyle,
+    pub background_alpha: f32,
     pub position: Corner,
 }
 
 impl Default for Legend {
     fn default() -> Self {
         Self {
             text_style: TextStyle::Body,
+            background_alpha: 0.75,
             position: Corner::RightTop,
         }
     }
 }
 
 impl Legend {
+    /// Which text style to use for the legend. Default: `TextStyle::Body`.
     pub fn text_style(mut self, style: TextStyle) -> Self {
         self.text_style = style;
         self
     }
 
+    /// The alpha of the legend background. Default: `0.75`.
+    pub fn background_alpha(mut self, alpha: f32) -> Self {
+        self.background_alpha = alpha;
+        self
+    }
+
+    /// In which corner to place the legend. Default: `Corner::RightTop`.
     pub fn position(mut self, corner: Corner) -> Self {
         self.position = corner;
         self
@@ -220,17 +230,29 @@ impl Widget for &mut LegendWidget {
             Corner::RightTop | Corner::RightBottom => Align::RIGHT,
         };
         let layout = Layout::from_main_dir_and_cross_align(main_dir, cross_align);
-        let legend_pad = 2.0;
+        let legend_pad = 4.0;
         let legend_rect = rect.shrink(legend_pad);
         let mut legend_ui = ui.child_ui(legend_rect, layout);
         legend_ui
             .scope(|ui| {
                 ui.style_mut().body_text_style = config.text_style;
-                entries
-                    .iter_mut()
-                    .map(|(name, entry)| entry.ui(ui, name.clone()))
-                    .reduce(|r1, r2| r1.union(r2))
-                    .unwrap()
+                let background_frame = Frame {
+                    margin: vec2(8.0, 4.0),
+                    corner_radius: ui.style().visuals.window_corner_radius,
+                    shadow: epaint::Shadow::default(),
+                    fill: ui.style().visuals.extreme_bg_color,
+                    stroke: ui.style().visuals.window_stroke(),
+                }
+                .multiply_with_opacity(config.background_alpha);
+                background_frame
+                    .show(ui, |ui| {
+                        entries
+                            .iter_mut()
+                            .map(|(name, entry)| entry.ui(ui, name.clone()))
+                            .reduce(|r1, r2| r1.union(r2))
+                            .unwrap()
+                    })
+                    .inner
             })
             .inner
     }

diff --git a/egui_demo_lib/src/apps/demo/plot_demo.rs b/egui_demo_lib/src/apps/demo/plot_demo.rs
@@ -272,6 +272,12 @@ impl Widget for &mut LegendDemo {
                 ui.selectable_value(&mut config.position, position, format!("{:?}", position));
             });
         });
+        ui.label("Background alpha:");
+        ui.add(
+            egui::DragValue::new(&mut config.background_alpha)
+                .speed(0.02)
+                .clamp_range(0.0..=1.0),
+        );
         let legend_plot = Plot::new("Legend Demo")
             .line(LegendDemo::line_with_slope(0.5).name("lines"))
             .line(LegendDemo::line_with_slope(1.0).name("lines"))