Re: Added tooltip to display details of items in TreeView

[Tony Yum <tony tony-yum co uk>]

Andrew E. Makeev wrote:

> Tony Yum wrote:
>
> > Dear all,
> >
> > I have just started using gtkmm and forgive me if the question might 
> > be a bit silly. But I don't seemed to be able to add tooltip to 
> > treeview items. i.e. I wish to display detail of the items in the 
> > treeview when I hover hover it. The tooltip object sets the text for 
> > the entire treeview, so I thought about listening to mouse motions on 
> > the treeview widget and then setting the tooltip appropriately. 
> > However as soon as I add content to the tree, the 
> > signal_motion_notify_event no longer sends signal to the slot that I 
> > connected to.
>
>
> I have implemented TreeView tooltip. Works both for Gtkmm-2.2 & 2.4.
>
> See my motion notify callback. I guess, you forgot to generate ENTER 
> notify event to let TreeView widget think that mouse just entered, 
> otherwise it will hide tooltip. Actually, it requires some 
> optimization, but that is not critical issue.

Thanx for the reply.

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?

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


<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.