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Vladimir Ulyanov
14,023 PointsSubclass initialization: Is the question/answer in this quiz correct?
I'm doing the "Build a Simple iPhone App with Swift 3" course and one of the quiz questions is "When we initialize a subclass, we first need to initialize the properties in our base class, then call the super class' initializer".
I put false, as I thought it was a trick question... But it says I was wrong.
Isn't the base class the same as the super class in the example above?
2 Answers
Simon Di Giovanni
8,429 PointsApples documentation describes a base class as “a class that does not inherit from another class”.
It defines a superclass as a “class from such the subclass inherits from”
I’d say that almost certainly they are exactly the same thing.
I think maybe the “super class” should actually say “sub class” in the question? That would explain the question correctly and also give the answer of True.
Simon Di Giovanni
8,429 PointsActually, reading it again...
The base class doesn’t inherit from ANY class.
Superclass CAN inherit from another superclass!
For example...
BASE CLASS -> SUPERCLASS -> SUBCLASS
If you create another subclass that inherits from a previous subclass, that subclass becomes a superclass!
So therefore, the question is saying.. first we must initialise the values in the base class, which is true. Then you have to initialise the superclass (which can be different to base class as outlined above) , which is also true.
Vladimir Ulyanov
14,023 PointsEven in that case though, aren't we always supposed to initialize the values of the subclass first? I thought that was the rule.
Simon Di Giovanni
8,429 PointsYes you are completely correct...
So I guess the question must be wrong then! Hmm.. haha.. odd one.
Vladimir Ulyanov
14,023 PointsI'll let you know what they say :)
Vladimir Ulyanov
14,023 PointsHey mate! Pasan got back to me, turns out the question itself was incorrect!
Simon Di Giovanni
8,429 PointsOh! Haha! Thanks for letting me know mate! Nice work.
Vladimir Ulyanov
14,023 PointsVladimir Ulyanov
14,023 PointsHmm... I thought that might be the case, I'll see if I can try flagging it to someone so they can change it (or educate me on why it is correct).
Cheers!
Simon Di Giovanni
8,429 PointsSimon Di Giovanni
8,429 PointsOnce you find out, be sure to let me know!