From a442971b81e8824ad1765bf55ca35be70b824c5a Mon Sep 17 00:00:00 2001
From: Mark Thompson <129641948+NotherNgineer@users.noreply.github.com>
Date: Thu, 15 Feb 2024 07:59:30 -0600
Subject: [PATCH] Eliminate unneeded screen flashing when scrolling menu
 (#1900)

---
 firmware/application/ui/ui_btngrid.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/firmware/application/ui/ui_btngrid.cpp b/firmware/application/ui/ui_btngrid.cpp
index 37776f40..871ea92f 100644
--- a/firmware/application/ui/ui_btngrid.cpp
+++ b/firmware/application/ui/ui_btngrid.cpp
@@ -173,13 +173,15 @@ bool BtnGridView::set_highlighted(int32_t new_value) {
         highlighted_item = new_value;
         offset += rows_;
         update_items();
-        set_dirty();
+        // refresh whole screen (display flickers) only if scrolling last row up and a blank button is needed at the bottom
+        if ((new_value + rows_ > item_count) && (item_count % rows_) != 0)
+            set_dirty();
     } else if ((uint32_t)new_value < offset) {
         // Shift BtnGridView down
         highlighted_item = new_value;
         offset = (new_value / rows_) * rows_;
         update_items();
-        set_dirty();
+        // no need to set_dirty() here since all buttons have been repainted
     } else {
         // Just update highlight
         highlighted_item = new_value;