Re: Finding widget position in table or box

[David Nečas (Yeti) <yeti physics muni cz>]

On Tue, May 30, 2006 at 10:43:33AM +0200, Daniel Haude wrote:
> say I have a table filled with some widgets. Now I'd like to replace one  
> of these widgets (A) with some other widget B. I guess I just go ahead and  
> destroy widget A, and then attach widget B. My problem is that in order to  
> do that, I need to know the position (row and column) that A had within  
> the table.
>
> To put the question simpler: Given a table and a widget within the table  
> (or box), how can I find the position of the widget within the table (or  
> box)?

To remember where you put it is usually the best solution.

You can also use something like the attached function (for
tables).  Note however, it accesses the private `children'
field of GtkTable.  In the case of boxes the field is public
(read-only), but you have to deal with start-packing and
end-packing.

Yeti


--
Anonyms eat their boogers.


=======================================================================
/**
 * gwy_table_get_child_widget:
 * @table: A #GtkTable.
 * @row: Row in @table.
 * @col: Column in @table.
 *
 * Finds a widget in #GtkTable by its coordinates.
 *
 * Coordinates (@col, @row) are taken as coordinates of widget top left corner.
 * More precisely, the returned widget either contains the specified grid
 * point or it is attached by its left side, top side, or top left corner to
 * this point.
 *
 * If there are multiple matches due to overlapping widgets, a random
 * match is returned.
 *
 * Returns: The widget at (@col, @row) or %NULL if there is no such widget.
 **/
GtkWidget*
gwy_table_get_child_widget(GtkWidget *table,
                           gint row,
                           gint col)
{
    GList *l;

    g_return_val_if_fail(GTK_IS_TABLE(table), NULL);
    for (l = GTK_TABLE(table)->children; l; l = g_list_next(l)) {
        GtkTableChild *child = (GtkTableChild*)l->data;

        if (child->left_attach <= col && child->right_attach > col
            && child->top_attach <= row && child->bottom_attach > row)
            return child->widget;
    }
    return NULL;
}