I am writing a simple component. I want to ensure that my MethodOptions methods change in the Object Inspector according to my chosen method.
Something like that:

So far I have encoded:
TmyMethod = (cmFirst, cmSecond);
TmyMethodOptions = class(TPersistent)
published
property SomethingInBase: boolean;
end;
TmyMethodOptionsFirst = class(TmyMethodOptions)
published
property SomethingInFirst: boolean;
end;
TmyMethodOptionsSecond = class(TmyTMethodOptions)
published
property SomethingInSecond: boolean;
end;
TmyComponent = class(TComponent)
private
fMethod: TmyMethod;
fMethodOptions: TmyMethodOptions;
procedure ChangeMethod(const Value: TmyMethod);
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
published
property Method: TmyMethod read fMethod write ChangeMethod default cmFirst;
property MethodOptions: TmyMethodOptions read fMethodOptions
write fMethodOptions;
end;
implementation
procedure TmyComponent.ChangeMethod(const Value: TmyMethod);
begin
fMethod := Value;
fMethodOptions.Free;
// case...
if Value = cmFirst then
fMethodOptions := TmyMethodOptionsFirst.Create
else
fMethodOptions := TmyMethodOptionsSecond.Create;
// fMethodOptions.Update;
end;
constructor TmyComponent.Create(AOwner: TComponent);
begin
inherited;
fMethodOptions := TmyMethodOptions.Create;
fMethod := cmFirst;
end;
destructor TmyComponent.Destroy;
begin
fMethodOptions.Free;
inherited;
end;
Of course, it has almost nothing (other than a hanging IDE), and I don't have any starting point for finding the right knowledge to achieve this.
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