end;

procedure TFlatTabControl.SetTabs (Value: TStrings);
var
  counter: Integer;
begin
  FTabs.Assign(Value);
  if FTabs.Count = 0 then // no tabs? then active tab = 0
    FActiveTab := 0
  else
    begin
      if (FTabs.Count - 1) < FActiveTab then // if activeTab > last-tab the activeTab = last-tab
        FActiveTab := FTabs.Count - 1;
      for counter := 0 to FTabs.Count - 1 do
        FTabs[counter] := Trim(FTabs[counter]); // delete all spaces at left and right
    end;
  SetTabRect;
  Invalidate;
end;

procedure TFlatTabControl.SetTabHeight (Value: Integer);
begin
  if Value < 0 then Value := 0; // TabHeigh can't negative
  FTabHeight := Value;
  SetTabRect;
  Invalidate;
end;

procedure TFlatTabControl.SetTabSpacing (Value: Integer);
begin
  if Value < 1 then Value := 1; // minimal tabspacing = 1 dot
  FTabSpacing := Value;
  SetTabRect;
  Invalidate;
end;

procedure TFlatTabControl.SetTabRect;
var
  TabCount: Integer;
  TabRect: ^TRect;
  position: TPoint;
  CaptionTextWidth: Integer;
  CaptionTextString: string;
begin
  // set the font and clear the tab-rect-list
  canvas.font := self.font;
  FTabsRect.Clear;

  // set left/top position for the the first tab
  case FTabPosition of
    tpTop:
      position := Point(ClientRect.left, ClientRect.top);
    tpBottom:
      position := Point(ClientRect.left, ClientRect.bottom - FTabHeight);
  end;

  for TabCount := 0 to (FTabs.Count - 1) do
  begin
    New(TabRect); // create a new Tab-Rect
    if Pos('&', FTabs[TabCount]) <> 0 then // if & in an caption
    begin
      CaptionTextString := FTabs[TabCount]; // read the caption text
      Delete(CaptionTextString, Pos('&', FTabs[TabCount]), 1); // delete the &
      CaptionTextWidth := canvas.TextWidth(CaptionTextString); // calc the caption-width withou the &
    end
    else // else calc the caption-width
      CaptionTextWidth := canvas.TextWidth(FTabs[TabCount]);
    case FTabPosition of // set the rect
      tpTop:
        TabRect^ := Rect(position.x, position.y, position.x + CaptionTextWidth + 20, FTabHeight);
      tpBottom:
        TabRect^ := Rect(position.x, position.y, position.x + CaptionTextWidth + 20, position.y + FTabHeight);
    end;
    position := Point(position.x + CaptionTextWidth + 20 + FTabSpacing, position.y); // set left/top position for next rect
    FTabsRect.Add(TabRect); // add the tab-rect to the tab-rect-list
  end;
end;

procedure TFlatTabControl.CMDialogChar (var Message: TCMDialogChar);
var
  currentTab: Integer;
begin
  with Message do
  begin
    if FTabs.Count > 0 then
    begin
      for currentTab := 0 to FTabs.Count - 1 do
      begin
        if IsAccel(CharCode, FTabs[currentTab]) then
        begin
          if (FActiveTab <> currentTab) then
          begin
            SetActiveTab(currentTab);
            SetFocus;
          end;
          Result := 1; 
          break;
        end;
      end;
    end
    else
      inherited;
  end;
end;

procedure TFlatTabControl.Paint;
var
  abc: TBitmap;
  TabCount: Integer;
  TempRect: ^TRect;
begin
  abc := TBitmap.Create; // create memory-bitmap to draw flicker-free
  try
    abc.Height := ClientRect.Bottom;
    abc.Width := ClientRect.Right;
    abc.Canvas.Font := Self.Font;

    // Clear Background
    abc.canvas.Brush.Color := TForm(Parent).Color;
    abc.canvas.FillRect(ClientRect);

    // Draw Border
    if FTabs.Count = 0 then
    begin
      abc.canvas.Brush.Color := FBorderColor;
      abc.canvas.FrameRect(ClientRect)
    end
    else
    begin
      abc.canvas.Pen.Color := FBorderColor;
      TempRect := FTabsRect.Items[FActiveTab];
      if ClientRect.left <> TempRect^.left then // if Active Tab not first tab then __|Tab|___
      begin
        case FTabPosition of
          tpTop:
          begin
            abc.Canvas.Polyline([Point(ClientRect.left, ClientRect.top + FTabHeight), Point(TempRect^.Left, ClientRect.top + FTabHeight)]);
            abc.Canvas.Polyline([Point(TempRect^.Right-1, ClientRect.top + FTabHeight), Point(ClientRect.right, ClientRect.top + FTabHeight)]);
          end;
          tpBottom:
          begin
            abc.Canvas.Polyline([Point(ClientRect.left, ClientRect.bottom - FTabHeight - 1), Point(TempRect^.Left, ClientRect.bottom - FTabHeight - 1)]);
            abc.Canvas.Polyline([Point(TempRect^.Right-1, ClientRect.bottom - FTabHeight - 1), Point(ClientRect.right, ClientRect.bottom - FTabHeight - 1)]);
          end;
        end;
      end
      else // else |Tab|___
        case FTabPosition of
          tpTop:
            abc.Canvas.Polyline([Point(TempRect^.Right-1, ClientRect.top + FTabHeight), Point(ClientRect.right, ClientRect.top + FTabHeight)]);
          tpBottom:
            abc.Canvas.Polyline([Point(TempRect^.Right-1, ClientRect.bottom - FTabHeight - 1), Point(ClientRect.right, ClientRect.bottom - FTabHeight - 1)]);
        end;
      // border of the control
      case FTabPosition of
        tpTop:
          abc.Canvas.Polyline([Point(ClientRect.left, ClientRect.top + FTabHeight), Point(ClientRect.left, ClientRect.bottom - 1), Point(ClientRect.right - 1, ClientRect.bottom - 1), Point(ClientRect.right - 1, ClientRect.top + FTabHeight)]);
        tpBottom:
          abc.Canvas.Polyline([Point(ClientRect.left, ClientRect.bottom - FTabHeight - 1), Point(ClientRect.left, ClientRect.top), Point(ClientRect.right - 1, ClientRect.top), Point(ClientRect.right - 1, ClientRect.bottom - FTabHeight - 1)]);
      end;
    end;

    case FTabPosition of
      tpTop:
        begin
          abc.canvas.brush.color := Color;
          abc.Canvas.FillRect(Rect(ClientRect.left + 1, ClientRect.top + FTabHeight + 1, ClientRect.right - 1, ClientRect.bottom - 1));
        end;
      tpBottom:
        begin
          abc.canvas.brush.color := Color;
          abc.Canvas.FillRect(Rect(ClientRect.left + 1, ClientRect.top + 1, ClientRect.right - 1, ClientRect.bottom - FTabHeight - 1));
        end;
    end;

    // Draw Tabs
    for TabCount := 0 to FTabs.Count - 1 do
    begin
      TempRect := FTabsRect.Items[TabCount];
      abc.canvas.brush.style := bsclear;
      abc.canvas.pen.color := clBlack;
      if TabCount = FActiveTab then // if Active Tab not first tab then draw border |^^^|
      begin
        abc.canvas.font.color := self.font.color;
        abc.canvas.brush.color := Color;
        abc.canvas.pen.color := FBorderColor;
        case FTabPosition of
          tpTop:
            begin
              abc.Canvas.FillRect(Rect(TempRect^.left, TempRect^.top, TempRect^.right - 1, TempRect^.bottom + 1));
              abc.Canvas.Polyline([Point(TempRect^.Left, TempRect^.Bottom), Point(TempRect^.Left, TempRect^.Top), Point(TempRect^.Right-1, TempRect^.Top), Point(TempRect^.Right-1, TempRect^.Bottom)]);
            end;
          tpBottom:
            begin
              abc.Canvas.FillRect(Rect(TempRect^.left, TempRect^.top - 1, TempRect^.right - 1, TempRect^.bottom));
              abc.Canvas.Polyline([Point(TempRect^.Left, TempRect^.top - 1), Point(TempRect^.Left, TempRect^.bottom - 1), Point(TempRect^.Right-1, TempRect^.bottom - 1), Point(TempRect^.Right-1, TempRect^.top - 1)]);
            end;
        end;
      end
      else // else only fill the tab
      begin
        abc.canvas.font.color := color;
        abc.canvas.brush.color := FUnselectedColor;
        abc.Canvas.FillRect(TempRect^);
      end;
      if (TabCount = FActiveTab) and not Enabled then
       begin
        abc.Canvas.Font.Color := FUnselectedColor;
        DrawText(abc.canvas.Handle, PChar(FTabs[TabCount]), Length(FTabs[TabCount]), TempRect^, DT_CENTER or DT_VCENTER or DT_SINGLELINE)
       end
      else
        DrawText(abc.canvas.Handle, PChar(FTabs[TabCount]), Length(FTabs[TabCount]), TempRect^, DT_CENTER or DT_VCENTER or DT_SINGLELINE);
    end;
    canvas.CopyRect(ClientRect, abc.canvas, ClientRect); // Copy bitmap to screen
  finally
    abc.free; // delete the bitmap
  end;
end;

procedure TFlatTabControl.MouseDown (Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
var
  cursorPos: TPoint;
  currentTab: Integer;
  currentRect: ^TRect;
begin
  GetCursorPos(cursorPos);
  cursorPos := ScreenToClient(cursorPos);

  if FTabs.Count > 0 then
  begin
    for currentTab := 0 to FTabs.Count - 1 do
    begin
      currentRect := FTabsRect.Items[currentTab];
      if PtInRect(currentRect^, cursorPos) then
        if (FActiveTab <> currentTab) then // only change when new tab selected
        begin
          SetActiveTab(currentTab);
          SetFocus;
        end;
    end;
  end;
  inherited;
end;

end.