For the More Curious: Key-Value Coding

When a NIB file is read in, the outlets are set using a mechanism called Key-value coding (or KVC). Key-value coding is a set of methods defined in NSObject that enable you to set and get the values of properties by name. Here are two of the methods: 

-​ ​(​i​d​)​v​a​l​u​e​F​o​r​K​e​y​:​(​N​S​S​t​r​i​n​g​ ​*​)​k​;​
-​ ​(​v​o​i​d​)​s​e​t​V​a​l​u​e​:​(​i​d​)​v​ ​f​o​r​K​e​y​:​(​N​S​S​t​r​i​n​g​ ​*​)​k​;​

valueForKey: is a universal getter method. You can ask any object for the value of its fido property like this: 

i​d​ ​c​u​r​r​e​n​t​F​i​d​o​ ​=​ ​[​s​e​l​e​c​t​e​d​O​b​j​ ​v​a​l​u​e​F​o​r​K​e​y​:​@​"​f​i​d​o​"​]​;​

If there is a fido method (the fido-specific getter), it will be called and ...

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