From d42c3fe93baab2f1a4bfd31c8aa02e91214ca64b Mon Sep 17 00:00:00 2001
From: Bart <9132501-flyingsheep@users.noreply.gitlab.com>
Date: Wed, 22 Feb 2023 18:58:14 +0100
Subject: [PATCH] Win32: first attempt at implementing TListView.OnDataHint.
 Issue #30757.

---
 lcl/interfaces/win32/win32wscustomlistview.inc | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/lcl/interfaces/win32/win32wscustomlistview.inc b/lcl/interfaces/win32/win32wscustomlistview.inc
index fe1abb4db1..d56f31c225 100644
--- a/lcl/interfaces/win32/win32wscustomlistview.inc
+++ b/lcl/interfaces/win32/win32wscustomlistview.inc
@@ -295,7 +295,18 @@ var
       end;
     end;
   end;
-  
+
+  procedure HandleListViewOwnerDataHint(ALV: TCustomListViewAccess);
+  var
+    DataHintInfo: PNMLVCACHEHINT;
+  begin
+    debugln('HandleListViewOwnerDataHint');
+    DataHintInfo := PNMLVCACHEHINT(LPARAM);
+    if not Assigned(DataHintInfo) or (not ALV.OwnerData) then
+      Exit;
+    ALV.DoOwnerDataHint(DataHintInfo^.iFrom, DataHintInfo^.iTo);
+  end;
+
 begin
   Result := False;
   case Msg of
@@ -312,6 +323,8 @@ begin
           end;
         LVN_ODFINDITEM:
           HandleListViewFindItem(TCustomListViewAccess(AWinControl));
+        LVN_ODCACHEHINT:
+          HandleListViewOwnerDataHint(TCustomListViewAccess(AWinControl));
       end;
     end;
   end;