I'm using a GtkTreeView widget and I want to change the appearance of the "expander" icon that opens and closes child rows: I want the icons to be the triangels that we're all familiar with, but they're appearing as boxed "+" and "-" symbols instead.
At first I thought there must be a style enumeration that I can set, but I cannot find one. Then, I thought maybe there's a style property I can set in my theme's gtkrc file, but I don't think there is one. Finally, I resorted to trying to manually override the draw method like so:
GtkWidget *pTreeView = gtk_tree_view_new_with_model((GtkTreeModel *)pTreeModel);
(GTK_STYLE_GET_CLASS(pTreeView->style))->draw_expander = my_draw_expander_override;
But my_draw_expander_override() never gets called and the expanders are still the boxed "+" and "-" icons.
Does anyone know how can I change the appearance of the GtkTreeView expander icons or just draw them myself?
Thanks a bunch in advance!