Re: Added tooltip to display details of items in TreeView

["Andrew E. Makeev" <andrew solvo ru>]

Tony Yum wrote:

> I don't think I understand what you mean by generating an ENTER notify 
> event? Doesn't gtkmm widget know that when a mouse is entered anyway? 
> If not do I have to attach the signal_enter_notify_event to some slot? 
> What slot do I have to attached it to?
If you look closer at my callback you will find that it is generating 
that event itself :). You need that to change tooltip when moving mouse 
inside TreeView widget between different cells.

> I looked around the mail list and I found this:
>
> http://mail.gnome.org/archives/gtkmm-list/2002-November/msg00165.html
>
> which basically says use this function:
>
> add_events(Gtk::POINTER_MOTION_MASK)
>
> But my compiler complains that POINTER_MOTION_MASK does not exist in 
> the Gtk namespace. I then did a grep for this in the gtkmm header 
> files and could not find it? Maybe I am using gtkmm-2.6
Actually, I didn't add any events to my TreeView, it had set that event 
by default.
In your case you should use Gdk namespace: Gdk::POINTER_MOTION_MASK.

> <http://www.gtkmm.org/docs/gtkmm-2.4/docs/reference/html/classGtk_1_1Widget.html#a208> 
>
>
> > The main problem is that no one has answered how to change tooltip 
> > position on the fly, i.e. how to display tooltip at the Cell but 
> > below TreeView.
> >
> >    bool Grid::motion_notify_cb( GdkEventMotion* event )
> >    {
> >    Gtk::TreeModel::Path path;
> >    Gtk::TreeViewColumn *column;
> >    int cell_x, cell_y;
> >
> >    if ( view.get_path_at_pos( (int)event->x,
> >                   (int)event->y,
> >                   path, column,
> >                   cell_x, cell_y ) )
> >    {
> >        Gtk::TreeModel::Row row = *viewStore->get_iter( path );
> >        Glib::ustring tip = get_cell_tooltip( path, 
> > column->get_title() ); // this function is setting tooltip text 
> > depending on mouse position
> >        if( !tip.empty() )
> >        {
> >        instanceProperties.tooltips->set_tip( view, tip );
> >        GdkEventCrossing* user_event = 
> > (GdkEventCrossing*)gdk_event_new( GDK_ENTER_NOTIFY );
> >        user_event->window = event->window;
> >        user_event->send_event = TRUE;
> >        user_event->subwindow = event->window;
> >        user_event->time = event->time;
> >        user_event->x = event->x;
> >        user_event->y = event->y;
> >        user_event->x_root = event->x_root;
> >        user_event->y_root = event->y_root;
> >        user_event->mode = GDK_CROSSING_NORMAL;
> >        user_event->detail = GDK_NOTIFY_ANCESTOR;
> >        user_event->focus = TRUE;
> >        Gdk::Event cpp_event( (GdkEvent*)user_event );
> >        cpp_event.put();
> >        }
> >        else
> >        {
> >        instanceProperties.tooltips->unset_tip( view );
> >        }
> >    }
> >    else
> >    {
> >        instanceProperties.tooltips->unset_tip( view );
> >    }
> >    return false;
> >    }
> I'll give the above a try once I can get the tree to listen to mouse 
> motion.
If TreeView doesn't listen motion events in version 2.6 even when you did

<TreeWidget>.set_events( Gdk::ALL_EVENTS_MASK );

that may be GTK+ issue.