Changes the data for the item pointed to by @iter to be @data. If the sequence has a data destroy function associated with it, that function is called on the existing data that @iter pointed to.
a #GSequenceIter
new data for the item
2.14
See Implementation
Changes the data for the item pointed to by @iter to be @data. If the sequence has a data destroy function associated with it, that function is called on the existing data that @iter pointed to.