1. unit Unit3;
  3. interface
  5. uses
  6. Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
  7. System.Classes, Vcl.Graphics,
  8. Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Vcl.Themes;
  10. type
  11. TComboBoxStyleHookFix = class(TComboBoxStyleHook)
  12. protected
  13. procedure DrawItem(Canvas: TCanvas; Index: Integer; const R: TRect;
  14. Selected: Boolean); override;
  15. end;
  17. { TComboBoxStyleHookFix }
  19. TForm3 = class(TForm)
  20. ComboBox1: TComboBox;
  21. procedure FormCreate(Sender: TObject);
  22. private
  23. { Private declarations }
  24. public
  25. { Public declarations }
  26. end;
  28. var
  29. Form3: TForm3;
  31. implementation
  33. {$R *.dfm}
  35. procedure TComboBoxStyleHookFix.DrawItem(Canvas: TCanvas; Index: Integer;
  36. const R: TRect; Selected: Boolean);
  37. var
  38. DIS: TDrawItemStruct;
  39. Text: string;
  40. begin
  41. begin
  42. FillChar(DIS, SizeOf(DIS), 0);
  43. DIS.CtlType := ODT_COMBOBOX;
  44. DIS.CtlID := GetDlgCtrlID(Handle);
  45. DIS.itemAction := ODA_DRAWENTIRE;
  46. DIS.hDC := Canvas.Handle;
  47. DIS.hwndItem := Handle;
  48. DIS.rcItem := R;
  49. Text := TComboBox(Control).Items[Index];
  50. DIS.rcItem.Left := DIS.rcItem.Left +
  51. (DIS.rcItem.Width - Canvas.TextWidth(Text) - 5);
  52. DIS.itemID := Index;
  53. DIS.itemData := SendMessage(ListHandle, LB_GETITEMDATA, 0, 0);
  54. if Selected then
  55. DIS.itemState := DIS.itemState { or ODS_FOCUS } or ODS_SELECTED;
  56. SendMessage(Handle, WM_DRAWITEM, Handle, LPARAM(@DIS));
  57. end;
  58. end;
  60. procedure TForm3.FormCreate(Sender: TObject);
  61. begin
  62. TStyleManager.Engine.RegisterStyleHook(TComboBox, TComboBoxStyleHookFix);
  63. end;
  65. end.