A RecentFilter can be used to restrict the files being shown in a RecentChooser.
Files can be filtered based on their name (with add_pattern), on their mime type (with add_mime_type), on the application that has registered them (with add_application), or by a custom filter function (with add_custom).
Filtering by mime type handles aliasing and subclassing of mime types; e.g. a filter for text/plain also matches a file with mime type application/rtf, since application/rtf is a subclass of text/plain. Note that RecentFilter allows wildcards for the subtype of a mime type, so you can e.g. filter for image/\*.
Recently used files are supported since GTK+ 2.10.
GtkRecentFilter as GtkBuildable
The GtkRecentFilter implementation of the GtkBuildable interface supports adding rules using the <mime-types>, <patterns> and < applications> elements and listing the rules within. Specifying a <mime-type>, <pattern> or <application> has the same effect as calling add_mime_type, add_pattern or add_application.
An example of a UI definition fragment specifying GtkRecentFilter rules: