From b8a8f2e3ff043891c9a1c5b41742cd5d121d5bae Mon Sep 17 00:00:00 2001
From: Vadim Zeitlin <vadim@wxwidgets.org>
Date: Tue, 2 Jun 2026 01:32:40 +0200
Subject: [PATCH] Factor out wxPropertyGrid::ReallocDoubleBufferIfNeeded()

No real changes, just extract the code (re)creating m_doubleBuffer into
its own function to allow for its reuse in the upcoming commit.
---
 include/wx/propgrid/propgrid.h |  2 ++
 src/propgrid/propgrid.cpp      | 61 ++++++++++++++++++----------------
 2 files changed, 35 insertions(+), 28 deletions(-)

diff --git a/include/wx/propgrid/propgrid.h b/include/wx/propgrid/propgrid.h
index 25e3a560a5..016feef016 100644
--- a/include/wx/propgrid/propgrid.h
+++ b/include/wx/propgrid/propgrid.h
@@ -1882,6 +1882,8 @@ private:
 
     bool ButtonTriggerKeyTest(wxPGKeyboardAction action, wxKeyEvent& event);
 
+    void ReallocDoubleBufferIfNeeded();
+
     wxDECLARE_EVENT_TABLE();
 };
 
diff --git a/src/propgrid/propgrid.cpp b/src/propgrid/propgrid.cpp
index 81f21378bd..88a3285e78 100644
--- a/src/propgrid/propgrid.cpp
+++ b/src/propgrid/propgrid.cpp
@@ -4561,6 +4561,38 @@ void wxPropertyGrid::RecalculateVirtualSize( int forceXPos )
 
 // -----------------------------------------------------------------------
 
+void wxPropertyGrid::ReallocDoubleBufferIfNeeded()
+{
+    if ( !HasExtraStyle(wxPG_EX_NATIVE_DOUBLE_BUFFERING) )
+    {
+        double scaleFactor = GetDPIScaleFactor();
+        int dblh = (m_lineHeight*2);
+        if ( !m_doubleBuffer )
+        {
+            // Create double buffer bitmap to draw on, if none
+            int w = wxMax(m_width, FromDIP(250));
+            int h = wxMax(m_height + dblh, FromDIP(400));
+            m_doubleBuffer = new wxBitmap;
+            m_doubleBuffer->CreateWithLogicalSize( w, h, scaleFactor );
+        }
+        else
+        {
+            int w = m_doubleBuffer->GetLogicalWidth();
+            int h = m_doubleBuffer->GetLogicalHeight();
+
+            // Double buffer must be large enough
+            if ( w < m_width || h < (m_height+dblh) )
+            {
+                if ( w < m_width ) w = m_width;
+                if ( h < (m_height+dblh) ) h = m_height + dblh;
+                delete m_doubleBuffer;
+                m_doubleBuffer = new wxBitmap;
+                m_doubleBuffer->CreateWithLogicalSize( w, h, scaleFactor );
+            }
+        }
+    }
+}
+
 void wxPropertyGrid::OnResize( wxSizeEvent& event )
 {
     if ( !(m_iFlags & wxPG_FL_INITIALIZED) )
@@ -4572,34 +4604,7 @@ void wxPropertyGrid::OnResize( wxSizeEvent& event )
     m_width = width;
     m_height = height;
 
-    if ( !HasExtraStyle(wxPG_EX_NATIVE_DOUBLE_BUFFERING) )
-    {
-        double scaleFactor = GetDPIScaleFactor();
-        int dblh = (m_lineHeight*2);
-        if ( !m_doubleBuffer )
-        {
-            // Create double buffer bitmap to draw on, if none
-            int w = wxMax(width, FromDIP(250));
-            int h = wxMax(height + dblh, FromDIP(400));
-            m_doubleBuffer = new wxBitmap;
-            m_doubleBuffer->CreateWithLogicalSize( w, h, scaleFactor );
-        }
-        else
-        {
-            int w = m_doubleBuffer->GetLogicalWidth();
-            int h = m_doubleBuffer->GetLogicalHeight();
-
-            // Double buffer must be large enough
-            if ( w < width || h < (height+dblh) )
-            {
-                if ( w < width ) w = width;
-                if ( h < (height+dblh) ) h = height + dblh;
-                delete m_doubleBuffer;
-                m_doubleBuffer = new wxBitmap;
-                m_doubleBuffer->CreateWithLogicalSize( w, h, scaleFactor );
-            }
-        }
-    }
+    ReallocDoubleBufferIfNeeded();
 
     m_pState->OnClientWidthChange( width, event.GetSize().x - m_ncWidth, true );
     m_ncWidth = event.GetSize().x;