Type Alias GtkCallback 

pub type GtkCallback = Option<unsafe extern "C" fn(*mut GtkWidget, gpointer)>;

Aliased Type

pub enum GtkCallback {
    None,
    Some(unsafe extern "C" fn(*mut GtkWidget, *mut c_void)),
}

Variants

None

No value.

Some(unsafe extern "C" fn(*mut GtkWidget, *mut c_void))

Some value of type T.