move save_settings into callback (#925)

src/ui/gui.rs

@@ -521,8 +521,15 @@ pub fn app_window(is_android: bool) {
     }
     ui::netplay::netplay_window(&app);
     ui::cheats::cheats_window(&app);
+
+    let weak_app = app.as_weak();
+    app.window().on_close_requested(move || {
+        weak_app
+            .upgrade_in_event_loop(move |handle| save_settings(&handle))
+            .unwrap();
+        slint::CloseRequestResponse::HideWindow
+    });
     app.run().unwrap();
-    save_settings(&app);
 }
 
 pub fn run_rom(