Re: Is there ways to make a atk factory only used for some instances

["padraig o'briain" <Padraig Obriain Sun COM>]

I have just seen Bill's reponse but I will go ahead anyhow as I hope 
this expands on Bill's mail.

I suggest changing
        week_view->jump_buttons[i] = gnome_canvas_item_new
            (canvas_group,
             gnome_canvas_pixbuf_get_type (),
             "GnomeCanvasPixbuf::pixbuf", pixbuf,
             NULL);
to
        week_view->jump_buttons[i] = gnome_canvas_item_new
            (canvas_group,
             gnome_canvas_action_pixbuf_get_type (),
             "GnomeCanvasPixbuf::pixbuf", pixbuf,
             NULL);

See attachment for definition of GnomeCanvasActionPixbuf. Note that the 
files in the attachment have not been run through acompiler so they may 
contain errors.


How do you distinguish betwenen a jump button and other types of 
GnomeCanvasPixbuf.

I have had a look at the code in gail and there is no specific support 
for GnomeCanvasPixbuf. Do you need additions to gail?

Padraig


Bolian Yin wrote:
> Hi Bill and Padraig,
>
> Please see the attached picture. The "jump button" (the little yellow rectangle) 
> is the gnome-canvas-item in question, more accurately, it is a 
> gnome-canvas-item-pixbuf.  The "jump button" is used to indicate that there are 
> more events that are not displayed in the day.  Now I have make it focusable, 
> can jump to the day on receving a Enter Key, then all the events of the day can 
> be displayed.  This is the action that I want to export through the atk action 
> interface.
>
> In the current implementation of the jump button in evolution, there are no new 
> subclass to GnomeCanvasPixbuf, see the code below:
>
> -- code snip begins 
> -----------------------------------------------------------------------------------
>
>     /* Create the buttons to jump to each days. */
>     pixbuf = gdk_pixbuf_new_from_xpm_data ((const char**) jump_xpm);
>
>     for (i = 0; i < E_WEEK_VIEW_MAX_WEEKS * 7; i++) {
>         week_view->jump_buttons[i] = gnome_canvas_item_new
>             (canvas_group,
>              gnome_canvas_pixbuf_get_type (),
>              "GnomeCanvasPixbuf::pixbuf", pixbuf,
>              NULL);
>
>         g_signal_connect (week_view->jump_buttons[i], "event",
>                   G_CALLBACK (e_week_view_on_jump_button_event), week_view);
>     }
>
> /* ... omitted */
>
> e_week_view_on_jump_button_event (GnomeCanvasItem *item,
>                   GdkEvent *event,
>                   EWeekView *week_view)
> {
>
>     /* ... omitted */
>
>     else if (event->type == GDK_KEY_PRESS) {
>         /* return, if Tab, Control or Alt is pressed */
>         if ((event->key.keyval == GDK_Tab) ||
>             (event->key.state & (GDK_CONTROL_MASK | GDK_MOD1_MASK)))
>             return FALSE;
>         /* with a return key or a simple character, jump to the day */
>         if ((event->key.keyval == GDK_Return) ||
>             ((event->key.keyval >= 0x20) &&
>              (event->key.keyval <= 0xFF))) {
>             e_week_view_jump_to_button_item (week_view, item);
>             return TRUE;
>         }
>     }
>
>     /* ... omitted */
> }
> -- code snip end 
> -----------------------------------------------------------------------------------
>
>
> So, the "action" is only supported through the signal handler to 
> GnomeCanvasPixbuf "event" signal, not in a new subclass. My aim is to support 
> this action only in the jumpbutton instances, not in any other instances of 
> GnomeCanvasPixbuf.
>
> Thanks,
> -Bolian
>
>
> Bill Haneman wrote:
>
> > Bolian:
> >
> > The best way to ensure that an AtkFactory is used only with certain
> > instances of a GObject type is to create a new subtype.  In your case,
> > this means that GnomeCanvasItem should be subclassed, and an appropriate
> > AtkFactory registered for the new type or types.  
> >
> > GnomeCanvasItem is already an abstract class, so you must already be
> > using subclasses.  If your GnomeCanvasItems are instances of existing
> > GnomeCanvas subtypes, for instance GnomeCanvasWidget instances, you may
> > need to create something like a GnomeCanvasActiveWidget type which is
> > used for your 'actionable' canvas items.
> >
> > regards
> >
> > Bill
> >
> > On Thu, 2003-09-04 at 08:06, Bolian Yin wrote:
> >  
> >
> > > Hi Padraig,
> > >
> > > I met the problem in gnome-canvas-item. Gail has impl for 
> > > gnome-canvas-item, but programmers can add many functions to a 
> > > gnome-canvas-item.
> > >
> > > For example, a gnome-canvas-item support an action in some context, and 
> > > want to add a action interface to the atkobject creates for it. In this 
> > > case, I cannot register a new factory to create the atk object, or all 
> > > the gnome-canvas-items will create their atk objects using the new factory.
> > > Is there ways to make a atk factory only used for some instances of 
> > > gnome-canvas-item, and in other case the default (gail) factory will be 
> > > used?
> > >
> > > Thanks,
> > > Bolian
> > >
> > >
> > >    
> >
> >
> >  
>
>
> ------------------------------------------------------------------------

Attachment: action.tar.gz
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