hey guys, I am just creating an app at the moment, im a bit new at this, and i have just one question, i think i can get the rest working. Im not sure if its a really easy question to answer but ill give it a go anyway. I need to implement a protocol and i have no idea what to write, can anyone tell me what it would look like to implement a protocol for this error im getting? warning: class 'FirstViewController' does not implement the 'SubstitutableViewController' protocol I looked up the documentation and all i seen was But what should this look like given the error im getting? Thank you for any help.