[Lazarus] Hook TComponent streaming system

[Mattias Gaertner]

On Sat, 22 May 2010 18:33:47 -0300
Luiz Americo Pereira Camara <luizmed at oi.com.br> wrote:

> Michael Van Canneyt escreveu:
> >
> >
> > On Sat, 22 May 2010, Luiz Americo Pereira Camara wrote:
> >
> >> I'd like to set some properties of a TComponent(TForm) through RTTI 
> >> before TComponent.Loaded is called.
> >>
> >> After a call to TMyForm.Create, the component is initiated through 
> >> the streaming system that calls Loaded.
> >>
> >> Is there a way to hook this streaming system so i can change the 
> >> properties before the call to Loaded?
> >
> > You can use defineproperties for that. You can simply override it in  
> > your
> > form and set whatever properties you want. An alternative is overriding
> > 'Loading', which is called at the start.
> 
> Thanks. But i think that won't help me. I'm creating a instance of a 
> generic TForm (see code below) and than setting the properties after the 
> call to constructor.
> 
> I would need that the properties be set after loading the stored 
> properties and before FormClass.Loaded is called but it's to late.
> 
> The problem is that Loaded is called inside the constructor call chain. 
> I could create the instance through NewInstance but AFAIK that is too 
> early (before creating the stored/published properties).
> 
> var
>   Form: TForm;
> begin
>   //FormClass: TFormClass
>   Form := FormClass.Create(Owner);
>   SetObjectProperties(Form, FormProperties);
>   [..]
> end;

What do you want to achieve? 
Why do you think you have to set a property after loading and before
Loaded?

Mattias