Is font attributes available

[chrisaw (Chris Williams)]

I think we pretty much covered that. Use pango_font_face_list_sizes(), with a fallback array for when that returns NULL. Are you asking how to take an array of numbers and make a DropDown?

[oneeyeman1 (Igor K)]

Hi,

@chrisaw

You would start with a FontMap; that’s the full set of available fonts. I don’t know if it matters whether you get it with PangoCairo.FontMap.get_default() or widget.get_pango_context().get_font_map() . In practice, those appear to yield the same object.

Does this mean that different widgets have different context objects and so have different FontMap’s?

Thank you.

[chrisaw (Chris Williams)]

It’s possible to set a custom font map for a widget (gtk_widget_set_font_map()), but as long as that’s not done, widgets chain up to the toplevel window which uses pango_cairo_font_map_get_default(). So, they’ll normally be the same.

[oneeyeman1 (Igor K)]

@chrisaw,
I’m sorry - one more question…

The page at PangoCairo.FontMap.get_default does not indicate whiich header the function is declared in.

Can you help?

Thank you.

[chrisaw (Chris Williams)]

That information is available on the main page for the namespace. Click where it says PangoCairo.

C headers	pango/pangocairo.h
pkg-config files	pangocairo

But if you’re using GTK, you don’t need to include that separately.

[oneeyeman1 (Igor K)]

@chrisaw ,

So what I do is following:

pango_context_list_families();
const gchar *name = pango_font_family_get_name();

then those names will be added into the font name selection combo box.

I already have a FontMap pointer. And so when I select the name X, how do I get the PangoFontFace from the FontMap for a specific font name?

Because I need PangoFontFace to get the sizes array…

Thank you.

[chrisaw (Chris Williams)]

You can get the list of faces from the family (pango_font_family_list_faces()).

But in GTK4, all of these objects implement GListModel, allowing you to use the modern list model APIs. Look at how this is implemented in GTK’s font chooser:

gtk/gtkfontchooserwidget.c · main · GNOME / gtk · GitLab

It’s actually remarkably simple, boiling down to essentially:

PangoFontMap *fontmap = pango_cairo_font_map_get_default ();
GListModel *model = G_LIST_MODEL (gtk_flatten_list_model_new (G_LIST_MODEL (g_object_ref (fontmap))));

That gives you a GListModel of PangoFontFaces, which you can use directly as the model for a GtkDropDown. You just need to provide an expression to get the name from the face object:

expression = gtk_cclosure_expression_new (G_TYPE_STRING, NULL,
                                          0, NULL,
                                          (GCallback)get_font_name,
                                          NULL, NULL);
gtk_drop_down_set_expression (GTK_DROP_DOWN (button), expression);

Where get_font_name is something like:

static char *
get_family_name (gpointer item)
{
  return g_strconcat (pango_font_family_get_name (pango_font_face_get_family (item)),
                      " ",
                      pango_font_face_get_face_name (item),
                      NULL);

}

This is all taken from the above link and the Pickers demo in gtk4-demo, which has a font family dropdown.

[oneeyeman1 (Igor K)]

@chrisaw ,

You can get the list of faces from the family (pango_font_family_list_faces() ).

This function will give me all available faces that makes up family.

Not what I am lookijng for…

But in GTK4, …

I need a solution for GTK3 still…

Thank you.