From bf266ca348f7a26e00af89161f3172dcd490b589 Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Sun, 21 Jun 2020 00:29:55 +0200
Subject: [PATCH] Avoid unnecessarily refreshing native header in wxGrid

We don't need to refresh it after resizing, it takes care of itself and
calling Refresh() just results in extra flicker.

See #18794.
---
 src/generic/grid.cpp | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/generic/grid.cpp b/src/generic/grid.cpp
index 5a92397095..50fc4c49e8 100644
--- a/src/generic/grid.cpp
+++ b/src/generic/grid.cpp
@@ -9844,7 +9844,10 @@ void wxGrid::DoSetColSize( int col, int width )
 
             FurtherWindowPartRefresher refreshFurtherPart(x);
 
-            refreshFurtherPart(m_colLabelWin);
+            // Refreshing the native header is unnecessary, as it updates
+            // itself correctly anyhow, and just results in extra flicker.
+            if ( !IsUsingNativeHeader() )
+                refreshFurtherPart(m_colLabelWin);
             refreshFurtherPart(m_gridWin);
 
             if ( m_frozenRowGridWin )