Add a "show in legend" toggle for items to hide them from the legend

.github/pull_request_template.md

@@ -4,7 +4,7 @@ Please read the "Making a PR" section of [`CONTRIBUTING.md`](https://github.com/
 * Keep your PR:s small and focused.
 * The PR title is what ends up in the changelog, so make it descriptive!
 * If applicable, add a screenshot or gif.
-* If it is a non-trivial addition, consider adding a demo f or a new example.
+* If it is a non-trivial addition, consider adding a demo for a new example.
 * Do NOT open PR:s from your `master` or `main` branch, as that makes it hard for maintainers to test and add commits to your PR.
 * Remember to run `cargo fmt` and `cargo clippy`.
 * Open the PR as a draft until you have self-reviewed it and run `./scripts/check.sh`.

egui_plot/src/items/mod.rs

@@ -34,16 +34,20 @@ pub struct PlotItemBase {
     id: Id,
     highlight: bool,
     allow_hover: bool,
+    pub(crate) show_in_legend: bool,
 }
 
 impl PlotItemBase {
+    /// The given name will show up in the legend and serves to track the visibility of items.
+    /// Multiple items may share the same name, in which case they also share a legend entry.
     pub fn new(name: String) -> Self {
         let id = Id::new(&name);
         Self {
             name,
             id,
             highlight: false,
             allow_hover: true,
+            show_in_legend: true,
         }
     }
 }
@@ -84,6 +88,13 @@ macro_rules! builder_methods_for_base {
             self.base_mut().id = id.into();
             self
         }
+
+        /// Whether to show the item in the legend. Default: `true`.
+        #[inline]
+        pub fn show_in_legend(mut self, show: bool) -> Self {
+            self.base_mut().show_in_legend = show;
+            self
+        }
     };
 }
 

egui_plot/src/legend.rs

@@ -242,6 +242,7 @@ impl LegendWidget {
         items
             .iter()
             .filter(|item| !item.name().is_empty())
+            .filter(|item| item.base().show_in_legend)
             .for_each(|item| {
                 let next_entry = entries.len();
                 let key = if config.follow_insertion_order {