CODEWITHSUNDEEP
delphifontscomboboxcontrolsdelphi-xe2
punker76
punker76

Reputation: 14611

How to change Font color for disabled TComboBox?

I have a TComboBox with Style:= csOwnerDrawVariable; and I want to show the disabled Font color in black and not in 'gray'.

This is what I get with this source:

procedure TCustomComboBox.WndProc(var Message: TMessage);
begin
  case Message.Msg of
    CN_CTLCOLORMSGBOX .. CN_CTLCOLORSTATIC, //48434..48440
    WM_CTLCOLORMSGBOX .. WM_CTLCOLORSTATIC:
    begin
      Color:= GetBackgroundColor; // get's the current background state
      Brush.Color:= Color;
    end;
  end;
  inherited;
end;

enter image description here

But I want the Font color of the inner Edit control in black.

If I change Font.Color:= clBlack at the WndProc or something else nothing happens.

A Google search give me some tips about changing a TEdit as read only, but this doesn't help me yet.

Update

Here is now my short solution after getting the tip from @Abelisto.

TCustomComboBox = class (TComboBox)
protected
  procedure DrawItem(Index: Integer; Rect: TRect; State: TOwnerDrawState); override;
end;

procedure TCustomComboBox.DrawItem(Index: Integer; Rect: TRect; State: TOwnerDrawState);
begin
  if odComboBoxEdit in State then begin // If we are drawing item in the edit part of the Combo
    if not Enabled then
      Canvas.Font.Color:= clBlack; // Disabled font colors
    Canvas.Brush.Color:= GetBackgroundColor; // Get the right background color: normal, mandatory or disabled
  end;
  inherited DrawItem(Index, Rect, State);
end;

Upvotes: 4

Views: 3754

Answers (1)

Abelisto
Abelisto

Reputation: 15614

Use OnDrawItem event. There is no special settings for the components at design time - all performed in code. Just put on the form ComboBox1 and Button1 and assign the events to them.

procedure TForm3.Button1Click(Sender: TObject);
begin
  ComboBox1.Enabled := not ComboBox1.Enabled; // Change Enabled state
end;

procedure TForm3.ComboBox1DrawItem(Control: TWinControl; Index: Integer;
  Rect: TRect; State: TOwnerDrawState);
var
  txt: string;
begin
  if Index > -1 then
    txt := ComboBox1.Items[Index]
  else
    txt := '';
  if odComboBoxEdit in State then // If we are drawing item in the edit part of the Combo
    if ComboBox1.Enabled then
    begin // Enabled colors
      ComboBox1.Canvas.Font.Color := clRed; // Foreground
      ComboBox1.Canvas.Brush.Color := clWindow; // Background
    end
    else
    begin // Disabled colors
      ComboBox1.Canvas.Font.Color := clYellow;
      ComboBox1.Canvas.Brush.Color := clGray;
    end;

  ComboBox1.Canvas.TextRect(Rect, Rect.Left, Rect.Top, txt); // Draw item. It may be more complex 
end;

procedure TForm3.FormCreate(Sender: TObject);
begin
  with ComboBox1 do // Setup combo props
  begin
    Items.Add('111');
    Items.Add('222');
    Items.Add('333');
    ItemIndex := 1;
    Style := csOwnerDrawVariable;
  end;
end;

Upvotes: 6

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