Sets the expression used to obtain strings from items.
The expression must have a value type of G_TYPE_STRING.
It's used to bind strings to labels produced by the default factory if
propertyComboRow:factory is not set, or when
propertyComboRow:use-subtitle is set to TRUE.
Sets the expression used to obtain strings from items.
The expression must have a value type of G_TYPE_STRING.
It's used to bind strings to labels produced by the default factory if propertyComboRow:factory is not set, or when propertyComboRow:use-subtitle is set to TRUE.