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Android Build an Interactive Story App (Retired) The Model-View-Controller Pattern Adding Custom Constructors

Arthur Podkowiak
Arthur Podkowiak
3,633 Points
Posted by Arthur Podkowiak
Arthur Podkowiak
3,633 Points

What is the point of mIsFinal

Why do you have to create a member variable that is just defined as a false boolean and then you change it to true. What was the point of that, I'm not understanding what mIsFinal does for the code. And couldn't we just make the second Page constructor not have Choice1 = null and Choice 2 = null ? Because if it is only taking two arguments anyways, why do we have to add this?

1 Answer

minzawmra
PLUS
minzawmra
Courses Plus Student 15,682 Points
minzawmra
minzawmra
Courses Plus Student 15,682 Points

mIsFinal is initialised to false by default. It is set to true only when the second constructor Page(int ImageId, String text) is called – you want it to stay 'false' if the other constructor is called. Alternatively, you can set mIsFinal in the other constructor as 'false' instead of combining the declaration and initialisation.

You can leave the initialisation of Choice1 = null and Choice2 = null out from the constructor. They would be set to null by default anyway. Explicit initialisation is not necessary. I believe those two lines were added just for clarity.

Arthur Podkowiak
Arthur Podkowiak
3,633 Points
Arthur Podkowiak
Arthur Podkowiak
3,633 Points

Ahh I see. I also found out we used it later in the code. I personally don't think it would be necessary in THAT particular stage of the app, but it is necessary later as it will set a boolean to allow us to use a later method to take out the choice buttons. But thank you for the help!