Re: Tutorial for writing widgets in Gtk3

[Timm Bäder <mail baedert org>]

That pointer is just not used because this is a minimal example that 
doesn't
even do any custom drawing. If you don't use it, don't declare it.

The cairo_t gets passed to the draw implementation by GTK+, it's
a parameter to the my_button_draw function. See also the
documentation for gtk_widget_draw().


On 2018-07-26 10:00, Göran Hasse wrote:
> If you look in the widget_class->draw section
>
> MyButton *button = MY_BUTTON(widget);
>
> Why is this pointer to button created? It is not used!
>
> And where is the cairo_t *cr comming from?
>
> This is a turorial that is not so easy to understand...
>
> /gh
>
> Den 2018-07-26 kl. 08:39, skrev Timm Bäder:
> > On 2018-07-26 09:42, Göran Hasse wrote:
> > > Hello!
> > >
> > > I try to write a custom widget in Gtk3. I study the source for other
> > > widgets but I find no totorial
> > > for how to write a widget in Gtk3. (There was for Gtk2 - but they are
> > > not of any use anymore...).
> > >
> > > Is there no interest in Gtk3 anymore? I find it very hard to find
> > > tutorials for Gtk3.
> >
> > There's https://wiki.gnome.org/HowDoI/CustomWidgets
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> Göran Hasse
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