Re: clickable images with alpha channel

[Ian Leonard <ian smallworld cx>]

Tim Evans wrote:
> Ian Leonard wrote:
>
> > Hi,
> >
> > I am trying to create a map with overlayed images acting as buttons. I 
> > managed to achieve this with 1.2 but am now working with gtk2-2.4.0-1.
> >
> > I use gtk_image_new_from_file () and put the images in a gtk_fixed 
> > container. So far so good - the images, which are irregular shapes 
> > display correctly, i.e. the background shows through.
> >
> > Now I need to make them clickable so I put them in an event_box. After 
> > this, they are surrounded by a grey box. It looks like the alpha 
> > rendering has been messed up.
> >
> > Is this a bug or am I doing this the wrong way?
>
>
> This is the expected behaviour.  A GtkEventBox has a real window behind 
> it, so it can't be transparent.  If you're using gtk+-2.4 then you could 
> try using gtk_event_box_set_visible_window (eventbox, FALSE).

Thanks for that. It works.

To be picky, it means that the clickable area isn't the same size as the
image. For the user this would be a bit of an oddity, however in my case 
 it's run from a touchscreen so no one will notice.



--
Ian Leonard

Please ignore spelling and punctuation - I did.