Delphi 在运行时添加附带的TColorListBox.Style颜色组,而不覆盖任何现有的自定义颜色?
我在Delphi 10.4.2 32位VCL应用程序中有一个Delphi 在运行时添加附带的TColorListBox.Style颜色组,而不覆盖任何现有的自定义颜色?,delphi,delphi-10.4-sydney,tcolor,Delphi,Delphi 10.4 Sydney,Tcolor,我在Delphi 10.4.2 32位VCL应用程序中有一个TColorListBox: object ColorListBox1: TColorListBox Left = 0 Top = 232 Width = 498 Height = 224 Align = alBottom Selected = clScrollBar Style = [cbCustomColors] ItemHeight = 20 TabOrder = 1 ExplicitWid
TColorListBox
:
object ColorListBox1: TColorListBox
Left = 0
Top = 232
Width = 498
Height = 224
Align = alBottom
Selected = clScrollBar
Style = [cbCustomColors]
ItemHeight = 20
TabOrder = 1
ExplicitWidth = 484
end
在TColorDialog
的帮助下,我在颜色列表中添加了一些自定义颜色项:
procedure TForm1.btnAddClick(Sender: TObject);
begin
if dlgColor1.Execute(Self.Handle) then
begin
// insert on top:
ColorListBox1.Items.InsertObject(0, 'My Color', TObject(dlgColor1.Color));
end;
end;
……因此:
现在,我尝试添加其中一个包含的t颜色列表框.Style
颜色组,而不覆盖以前添加的自定义颜色:
procedure TForm1.btnAddGroupClick(Sender: TObject);
begin
ColorListBox1.Style := ColorListBox1.Style + [cbStandardColors];
end;
但这会覆盖以前添加的自定义颜色
如何在运行时添加包含的TColorListBox.Style
颜色组,而不覆盖任何现有的自定义颜色
(请注意,“cbCustomColors”默认包括:
Style=[cbCustomColors]
)您必须将现有颜色保存在临时列表中:
procedure TForm1.btnAddGroupClick(Sender: TObject);
var
CL: TStringList;
begin
CL := TStringList.Create;
try
CL.Assign(ColorListBox1.Items); // save existing colors in a temporary list
ColorListBox1.Style := ColorListBox1.Style + [cbStandardColors];
ColorListBox1.Items.AddStrings(CL); // now add the temporary list
finally
CL.Free;
end;
end;
如果要将现有颜色保留在列表顶部,则必须逐个插入临时颜色:
procedure TForm1.btnAddGroupClick(Sender: TObject);
begin
if not (cbStandardColors in ColorListBox1.Style) then
AddColorGroup([cbStandardColors]);
end;
procedure TForm1.AddColorGroup(AColorGroup: TColorBoxStyle);
var
CL: TStringList;
i: Integer;
begin
CL := TStringList.Create;
try
CL.Assign(ColorListBox1.Items); // save existing colors in a temporary list
ColorListBox1.Items.BeginUpdate;
try
ColorListBox1.Style := ColorListBox1.Style + AColorGroup;
// keep existing colors on top:
for i := CL.Count - 1 downto 0 do // insert temporary colors back one by one
ColorListBox1.Items.InsertObject(0, CL[i], CL.Objects[i]);
finally
ColorListBox1.Items.EndUpdate;
end;
finally
CL.Free;
end;
end;