TreeView - set_cursor

[Vesko Jeliaz <vveesskkoo gmail com>]

hello,

While developing of a an application I faced some difficulties which can be
demonstrated with the code at the end of the email.

The program is supposed to function as follows:
The tree has three columnss. When the field in the second column is
filled with the word
"account", then the third column should be made visible, the cursor set to the
third row for editing.

My observations:
When the word "account" is entered in the second column in the first row,
the the third column is made visible and the focus is set on it, but
it doesn't start
editing. When the word "account" is enterd in the second row, the
program behaves
as i expect. Possible problem could be the setting of the visibility
property just
before the set_focus call in on_account_edited function.
my question is how can I ahieve the desired behaviour for the firs row???

Another problem appears when the first row, second column is clicked so that
the text "account" is marked. then the second row second columns is clicked
without pressing any key. The result is the following message in the console:

(cursor:7860): Gtk-CRITICAL **: _gtk_tree_view_column_start_editing:
assertion `tree_column->editable_widget == NULL' failed

which I don't understand.

any help will be appreciated.



OS:    Debian
version: gtkmm-2.6.4
compiler:  g++-4.0

THE CODE

treeview.h :
#include    <gtkmm/window.h>
#include    <gtkmm/treeview.h>
#include    <gtkmm/liststore.h>

class Trv: public Gtk::Window	{
	private:
        class Example_Model: public Gtk::TreeModel::ColumnRecord  {
            public:
                Gtk::TreeModelColumn<unsigned int>		id;
		Gtk::TreeModelColumn<Glib::ustring>		account;
                Gtk::TreeModelColumn<double>			sum;

                 Example_Model()  {
                    add(id);
                    add(account);
                    add(sum);
                }
        };

        Example_Model			    store_columns;
        Glib::RefPtr<Gtk::ListStore>     ref_store;
	Gtk::TreeView			       treeview;

        void	on_account_edited(Glib::ustring, Glib::ustring);
	void	on_treeview_press_button(GdkEventButton*);
	public:

			Trv();
		virtual	~Trv();
};

treeview.cc:
#include	"tree_view.h"


void Trv::on_account_edited(Glib::ustring path_str, Glib::ustring text)	{
    Gtk::TreeIter   iter=ref_store->get_iter(path_str);

	if (iter)	{
		(*iter)[store_columns.account]=text;

		if (text=="account")	{
			treeview.get_column(2)->set_visible(true);

			// works only if the column was visible before
			treeview.set_cursor(Gtk::TreePath(path_str), *treeview.get_column(2), true);
		}
	}
}
void Trv::on_treeview_press_button(GdkEventButton* e)	{
	if(e->type==GDK_BUTTON_PRESS)	{
		Gtk::TreePath			path;
		Gtk::TreeViewColumn*	p_column;
		int						x, y;

		if (treeview.get_path_at_pos(int(e->x), int(e->y), path, p_column, x, y))	{
			treeview.set_cursor(path, *p_column, true);
		}
	}
}

Trv::Trv():ref_store(Gtk::ListStore::create(store_columns))	{
    set_title("Account");
    set_size_request(600, 400);
    set_border_width(2);

	{
		Gtk::TreeRow	row=*(ref_store->append());

		row[store_columns.id]=ref_store->children().size();
		row[store_columns.account]="";
		row[store_columns.sum]=double(0);

		row=*(ref_store->append());
		row[store_columns.id]=ref_store->children().size();
		row[store_columns.account]="";
		row[store_columns.sum]=double(0);
	}
		
    treeview.set_model(ref_store);

    int		col=treeview.append_column("№", store_columns.id);

	col=treeview.append_column_editable("account", store_columns.account);
    (treeview.get_column(col-1))->set_expand(true);
	dynamic_cast<Gtk::CellRendererText*>(treeview.get_column_cell_renderer(col-1))->
		signal_edited().connect(sigc::mem_fun(*this, &Trv::on_account_edited));

    col=treeview.append_column_numeric_editable("sum",
store_columns.sum, "%.2f");
	treeview.get_column(col-1)->set_visible(false);
	
	treeview.signal_button_press_event().connect_notify(
		sigc::mem_fun(*this, &Trv::on_treeview_press_button));

	add(treeview);

	show_all_children();
}
Trv::~Trv()	{}

main.cc:
#include    <gtkmm/main.h>      // Gtk::Main
#include    "tree_view.c++"

int main (int argc, char *argv[], char *env[])   {
    Gtk::Main   kit(argc, argv);
    Trv			window;

    kit.run(window);

    return 0;
}

compile wit:
g++-4.0 main.c++ -o cursor `pkg-config gtkmm-2.4 --cflags --libs`