Re: Glib::RefPtr

[Phil Wolff <adiabat centurylink net>]

    CObject::CObject ( const Glib::ustring& filename )
    {
        m_pFrame = (Gtk::Frame*)( new CThumbnail ( filename ) );
    }

    Gtk::Frame* CObject::GetFrame ()
    {
        return ( m_pFrame );
    }

Elsewhere,

    class CThumbnail : public Gtk::Frame
    {
    ...
    };

I have neglected to mention the slot argument:

    m_pFlowBox->bind_list_store ( m_refCurrentModel, sigc::mem_fun ( 
*this, &CBridge::OnContentCreate () ) );
    ...
    Gtk::Widget* CBridge::OnContentCreate ( const Glib::RefPtr<CObject 
>& refObject )
    {
        return ( (Gtk::Widget*)refObject->GetFrame () );
    }

m_pFrame is stored in the CObject constructor, and retrieved for the 
return value of the callback slot, it is otherwise untouched in the 
application.

I construct two models and bind the first, and everything goes as 
expected. When I then bind the second model, all is still well. But when 
I bind the first model again, I get a bunch of failed assertions and a 
blank display.

I also constructed a much simpler example using Gtk::Label in place of 
Gtk::Frame and CThumbnail (which does contain Gtk::manage() calls) and

    m_pLabel = new Gtk::Label (filename);

in the CObject constructor. The results are the same.

On 10/08/2017 07:47 AM, Daniel Boles wrote:
> How do you create m_pFrame, and what do you do with it between 
> creating it and finding it to be 0?
>
> It sounds to be like you might be Gtk::manage()ing it and then adding 
> it to a container, in which case, that container sinks the floating 
> reference and takes over ownership completely. If so, you'd need to 
> not do that; have it as a non-pointer member and just hand out 
> observing references/pointers to it.
>
>
>
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