Initial Commit

src/app.rs

@@ -10,8 +10,9 @@ use egui::{
     Align, Button, Color32, FontData, FontDefinitions, PointerButton, RichText, ScrollArea, Stroke,
 };
 
+/// We derive Deserialize/Serialize so we can persist app state on shutdown.
 #[derive(serde::Deserialize, serde::Serialize)]
-#[serde(default)]
+#[serde(default)] // if we add new fields, give them default values when deserializing old state
 pub struct App {
     preferences: Preferences,
 
@@ -140,6 +141,8 @@ impl App {
                 Stroke::new(1.0, Color32::from_rgb(200, 200, 200));
         });
 
+        // Load previous app state (if any).
+        // Note that you must enable the `persistence` feature for this to work.
         if let Some(storage) = cc.storage {
             return eframe::get_value(storage, eframe::APP_KEY).unwrap_or_default();
         }
@@ -194,6 +197,8 @@ impl eframe::App for App {
         //});
 
         egui::TopBottomPanel::top("top_panel").show(ctx, |ui| {
+            // The top panel is often a good place for a menu bar:
+
             egui::containers::menu::Bar::new().ui(ui, |ui| {
                 // NOTE: no File->Quit on web pages!
                 ui.menu_button("Menu ⚙", |ui| {