Swift: Does not conform to protocol NSCoding

Question

I am trying to use the NSCoding protocol on a class I have written in swift, but cannot seem to figure out why the compiler complains that it \"does not conform to protocol

Answer 1

The parameters are not implicitly unwrapped (remove the !), and the initializer requires the required modifier:

required init(coder aDecoder: NSCoder) {
...
func encodeWithCoder(_aCoder: NSCoder) {

For Swift 3

A minor but important change has been commited . The init method is same but the encodeWithCoder method has been modified.

   required init(coder aDecoder: NSCoder) {
    ...
   }

   func encode(with _aCoder: NSCoder) { 
   ...
   }