Re: Set number of rows in GtkTreeView

[Ken Siersma <siersmak ekkinc com>]

Tim Müller wrote:

> On Wednesday 09 February 2005 13:56, Ken Siersma wrote:
>
>  
>
> > I want to specify a number of rows to always display in my
> > GtkTreeView widget, regardless of how many entities are in my
> > GtkListStore.  I'm using the GtkTreeView to display a list of files.
> > Sometimes there are no files, sometimes there are 100 files.  I want my
> > GtkTreeView to always display 15 rows.
> >
> > I'm porting code from Motif, and Motif can do this simply by specifying
> > the XmNvisibleItemCount property for it's list widget.  I'm looking for
> > a simple way to do this in GTK as well.  I've looked through the API,
> > but it didn't seem like there were any simple solutions like this.
> >    
>
> There isn't really anything as simple as a property. If your rows are all the 
> same height, however, you can probably do this in a hackish way, e.g. by 
> estimating the height of one row, and then multiplying that height with the 
> number of rows you want to be visible, and then call
>
>         gtk_widget_set_size_request (treeview, -1, height) 
>
> The tricky thing is to find out the height of a row of course. If you display 
> simple one-line strings or markup, you could do something along these lines:
>
>  guint 
>  simple_estimate_row_height (GtkTreeView *tv)
>  {
>      GtkCellRendererText *cell;
>      PangoLayout  *layout;
>      guint  row_height, ypad;
>
>      layout = gtk_widget_create_pango_layout (tv, NULL);
>
>      pango_layout_set_markup (layout, "<i>red fox jumps bla</i>", -1);
>      pango_layout_get_pixel_extents (layout, NULL, &row_height);
>
>      cell = gtk_cell_renderer_new_text ();
>      g_object_get (cell, "ypad", &ypad, NULL);
>      g_object_unref (cell);
>
>      g_object_unref (layout);
>
>      return row_height + 2*ypad;
>  }
>
> I'm sure there are more accurate and less hackish ways, but this might just do 
> anyway. If your treeview is in a scrolled window, you may have to take into 
> account the height of the horizontal scroll bar as well (if it's not set to 
> be invisible).
>
> Cheers
> -Tim
>  
Works for me, thanks!