Index: lcl/dbgrids.pas
===================================================================
--- lcl/dbgrids.pas	(revision 52443)
+++ lcl/dbgrids.pas	(working copy)
@@ -369,6 +369,7 @@
     procedure ClearSelection(selCurrent:boolean=false);
     function  NeedAutoSizeColumns: boolean;
     procedure RenewColWidths;
+    procedure Internal_AutoSizeColumn(aCol: Integer; aCanvas: TCanvas; aDatalinkActive: Boolean);
   protected
     procedure AddAutomaticColumns;
     procedure AssignTo(Dest: TPersistent); override;
@@ -493,6 +494,7 @@
   public
     constructor Create(AOwner: TComponent); override;
     procedure AutoSizeColumns;
+    procedure AutoSizeColumn(aCol: Integer);
     procedure InitiateAction; override;
     procedure DefaultDrawColumnCell(const Rect: TRect; DataCol: Integer; Column: TColumn; State: TGridDrawState);
     function  EditorByStyle(Style: TColumnButtonStyle): TWinControl; override;
@@ -1770,14 +1772,10 @@
 
 procedure TCustomDBGrid.UpdateAutoSizeColumns;
 var
-  ACol,ARow,w: Integer;
+  ACol: Integer;
   DatalinkActive: boolean;
   CurActiveRecord: Integer;
-  Field: TField;
-  ColWidth: Integer;
   tmpCanvas: TCanvas;
-  C: TGridColumn;
-  s: string;
 begin
   if gsAutoSized in GridStatus then
     exit;
@@ -1790,45 +1788,7 @@
 
   tmpCanvas := GetWorkingCanvas(Canvas);
   try
-    for aCol:=FixedCols to ColCount-1 do begin
-
-      Field := GetFieldFromGridColumn(ACol);
-      C := ColumnFromGridColumn(ACol);
-
-      if (C<>nil) and (C.Title<>nil) then begin
-        tmpCanvas.Font := C.Title.Font;
-        ColWidth := tmpCanvas.TextWidth(trim(C.Title.Caption));
-        tmpCanvas.Font := C.Font;
-      end else begin
-        if (Field<>nil) then begin
-          tmpCanvas.Font := TitleFont;
-          ColWidth := tmpCanvas.TextWidth(Field.FieldName);
-        end
-        else
-          ColWidth := 0;
-        tmpCanvas.Font := Font;
-      end;
-
-      if (Field<>nil) and DatalinkActive then
-        for ARow := FixedRows to RowCount-1 do begin
-
-          FDatalink.ActiveRecord := ARow - FixedRows;
-
-          if Field.dataType<>ftBlob then
-            s := trim(Field.DisplayText)
-          else
-            s := '(blob)';
-          w := tmpCanvas.TextWidth(s);
-          if w>ColWidth then
-            ColWidth := w;
-
-        end;
-
-      if ColWidth=0 then
-        ColWidth := GetColumnWidth(ACol);
-
-      ColWidths[ACol] := ColWidth + 15;
-    end;
+    for aCol:=FixedCols to ColCount-1 do Internal_AutoSizeColumn(ACol,tmpCanvas,DatalinkActive);
   finally
     if TmpCanvas<>Canvas then
       FreeWorkingCanvas(tmpCanvas);
@@ -3505,6 +3465,32 @@
   LayoutChanged;
 end;
 
+procedure TCustomDBGrid.AutoSizeColumn(aCol: Integer);
+var
+  DatalinkActive: boolean;
+  CurActiveRecord: Integer;
+  tmpCanvas: TCanvas;
+begin
+  BeginLayout;
+
+  DatalinkActive := FDatalink.Active;
+  if DatalinkActive then
+    CurActiveRecord := FDatalink.ActiveRecord;
+
+  tmpCanvas := GetWorkingCanvas(Canvas);
+  try
+    Internal_AutoSizeColumn(ACol,tmpCanvas,DatalinkActive);
+  finally
+    if TmpCanvas<>Canvas then
+      FreeWorkingCanvas(tmpCanvas);
+
+    if DatalinkActive then
+      FDatalink.ActiveRecord := CurActiveRecord;
+
+    EndLayout;
+  end;
+end;
+
 procedure TCustomDBGrid.InitiateAction;
 begin
   {$ifdef dbgDBGrid}DebugLnEnter('%s.InitiateAction INIT', [ClassName]);{$endif}
@@ -3640,6 +3626,53 @@
   exclude(FGridStatus, gsAutoSized);
 end;
 
+procedure TCustomDBGrid.Internal_AutoSizeColumn(aCol: Integer; aCanvas: TCanvas; aDatalinkActive: Boolean);
+var
+  Field: TField;
+  C: TGridColumn;
+  ColWidth: Integer;
+  ARow,w: Integer;
+  s: string;
+
+begin
+  Field := GetFieldFromGridColumn(ACol);
+  C := ColumnFromGridColumn(ACol);
+
+  if (C<>nil) and (C.Title<>nil) then begin
+    aCanvas.Font := C.Title.Font;
+    ColWidth := aCanvas.TextWidth(trim(C.Title.Caption));
+    aCanvas.Font := C.Font;
+  end else begin
+    if (Field<>nil) then begin
+      aCanvas.Font := TitleFont;
+      ColWidth := aCanvas.TextWidth(Field.FieldName);
+    end
+    else
+      ColWidth := 0;
+    aCanvas.Font := Font;
+  end;
+
+  if (Field<>nil) and aDatalinkActive then
+    for ARow := FixedRows to RowCount-1 do begin
+
+      FDatalink.ActiveRecord := ARow - FixedRows;
+
+      if Field.dataType<>ftBlob then
+        s := trim(Field.DisplayText)
+      else
+        s := '(blob)';
+      w := aCanvas.TextWidth(s);
+      if w>ColWidth then
+        ColWidth := w;
+
+    end;
+
+  if ColWidth=0 then
+    ColWidth := GetColumnWidth(ACol);
+
+  ColWidths[ACol] := ColWidth + 15;
+end;
+
 destructor TCustomDBGrid.Destroy;
 begin
   {$ifdef dbgGrid}DebugLn('%s.Destroy', [ClassName]); {$endif}