From 824d6adb92915751a7f6c84efe4f0750300c0c2a Mon Sep 17 00:00:00 2001
From: wp_xxyyzz <wp_xxyyzz@8e941d3f-bd1b-0410-a28a-d453659cc2b4>
Date: Thu, 20 Nov 2014 16:48:31 +0000
Subject: [PATCH] fpspreadsheet: Reduce flicker of TsTabControl; still not
 perfect.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@3754 8e941d3f-bd1b-0410-a28a-d453659cc2b4
---
 components/fpspreadsheet/fpspreadsheet.pas    |  3 +-
 .../fpspreadsheet/fpspreadsheetctrls.pas      | 29 +++++++------------
 2 files changed, 12 insertions(+), 20 deletions(-)

diff --git a/components/fpspreadsheet/fpspreadsheet.pas b/components/fpspreadsheet/fpspreadsheet.pas
index af6b17146..1e82881d1 100755
--- a/components/fpspreadsheet/fpspreadsheet.pas
+++ b/components/fpspreadsheet/fpspreadsheet.pas
@@ -6714,9 +6714,8 @@ begin
   Result := TsWorksheet.Create;
 
   Result.FWorkbook := Self; // Must be before "SetName" needing the workbook
-  Result.Name := AName;
   FWorksheets.Add(Pointer(Result));
-
+  Result.Name := AName;
   if Assigned(FOnAddWorksheet) then FOnAddWorksheet(self, Result);
 end;
 
diff --git a/components/fpspreadsheet/fpspreadsheetctrls.pas b/components/fpspreadsheet/fpspreadsheetctrls.pas
index 5b7fac182..d5b45d271 100644
--- a/components/fpspreadsheet/fpspreadsheetctrls.pas
+++ b/components/fpspreadsheet/fpspreadsheetctrls.pas
@@ -150,6 +150,7 @@ type
   TsWorkbookTabControl = class(TTabControl)
   private
     FWorkbookSource: TsWorkbookSource;
+    FLockCount: Integer;
     procedure SetWorkbookSource(AValue: TsWorkbookSource);
   protected
     procedure Change; override;
@@ -983,7 +984,7 @@ end;
 -------------------------------------------------------------------------------}
 procedure TsWorkbookTabControl.Change;
 begin
-  if FWorkbookSource <> nil then
+  if (FWorkbookSource <> nil) and (FLockCount = 0) then
     FWorkbookSource.SelectWorksheet(Workbook.GetWorksheetByIndex(TabIndex));
   inherited;
 end;
@@ -1039,29 +1040,19 @@ procedure TsWorkbookTabControl.ListenerNotification(
   AChangedItems: TsNotificationItems; AData: Pointer = nil);
 var
   i: Integer;
-  oldTabIndex: Integer;
-  list: TStringList;
+  t: Integer;
 begin
   Unused(AData);
 
   // Workbook changed
   if (lniWorkbook in AChangedItems) then
   begin
-    oldTabIndex := TabIndex;
-    list := TStringList.Create;
-    Tabs.BeginUpdate;
-    try
-      GetSheetList(list);
-      Tabs.Assign(list);
-      if (oldTabIndex = -1) and (Tabs.Count > 0) then
-        TabIndex := 0
-      else
-      if oldTabIndex < Tabs.Count then
-        TabIndex := oldTabIndex;
-    finally
-      list.Free;
-      Tabs.EndUpdate;
-    end;
+    inc(FLockCount);    // avoid WorkbookSelect message when adding each tab
+    GetSheetList(Tabs);
+    t := TabIndex;
+    TabIndex := Tabs.Count-1;
+    t := TabIndex;
+    dec(FLockCount);
   end;
 
   // Worksheet changed
@@ -1071,6 +1062,8 @@ begin
     if i <> TabIndex then
       TabIndex := i;
   end;
+
+  t := TabIndex;
 end;
 
 {@@ ----------------------------------------------------------------------------