Ray Wenderlich Fundamentals Course - Part 5

OK last part! I'm going to complete this fundamentals course today! Also, Xcode looks like it's ready for the official update - so I won't need Beta anymore. Anyway, time to go for it.

Start Time - 20:44

Structures

Grouping sets of related data together.
Technically, all of the below are structs!
 


struct Student {
    
    let name: String
    let grade: Int
    let pet: String?
}


let bobStudent = Student(name: "Bob", grade: 33, pet: nil)

Most of this is recap so skimming through
*Technical glitch for 5 approx minutes. Wifi back on!

Mutating. I've made sense of this at last! If you do a function that alters one of the STORED PROPERTIES e.g. grade, then I have to use the mutating keyword. Cool. 

Value type. I could clone an instance. That new version is unique and does not affect the original. Class (reference types) do.. It's also got to be a var, to change any of the values. 

Challenge!

OK actually stuck! I need a method to return the highest grade of the students array...going to get some help...

Magical! It worked in the end. I needed an empty array to put the grades into first. That makes sense and is a top tip - always create a new array, if you need to get values from an object. Rest of challenge all good. 

Classes

Going to skim through more quickly as am pushed for time...
Honestly have not paid much attention. Some focus on creating a structure, then changing it to a class. SO will do the challenge!

Done! Easy!

A key point here is you DON'T use the mutating word for functions that change the stored properties in classes. OK, interesting.

Another thing is that you can create a constant of the instance, and still then make changes to it. You can't do that with value types. 

Right, done! Course complete! Before doing the next course with the FULL Xcode, I'll do a consolidation entry. A final point about style (linked to API) and also that there are future courses ready. Raywenderlich.com is definitely the place for relevant, up to date content. 

Finish Time - 21:27 (approx 40 minutes)




Comments

Post a Comment

Popular posts from this blog

*Xcode Project Entry 2* F1 Quiz - part 1

Image
It's Christmas Eve and time to code! To think, a year ago, I was plodding along with some eBook, blindly convincing myself that I was on a steady road to coding greatness. Really, it was from June where I made the decision to start again, humbling as that may seem. It would have been comforting to have completed endless 'beginner' courses but branching out and applying the theory is the key thing, which brings us to this entry. Yes, my second Xcode OWN project! I thought about doing an educational one, as there is certainly a lot of scope and relevance for that, being a teacher and all. However, making a quiz makes sense, for various reasons.  First off, I have made this before through Angela's excellent tutorial. No offence to Sandra, but hers is not even close to the elegance and effectiveness of Angela's project. The one thing to take from Sandra is the stack views. Definitely something I will use from now on. This is one of the great things about learning from...
Read more

Angela Yu Course Part 10 (up to lesson 112)

Image
It's unlikely that I'll be able to do any Swift tomorrow as I'm going to Eastbourne today, for the weekend. So I can give half an hour now, maximum! Coding Challenge - Destini App! Choose your own adventure books! I used to ADORE these. Angela explains that these have had some sort of revival through the Lifeline games. It's very binary - yes/no mostly. I have my own experience of this based on WDC... Now the challenge is to complete the game! Having followed the first few instructions, which I found a bit confusing it must be said, I was about to surrender and see the answer. Then I managed to stop myself - I CAN do this, or at least have a good go! Even if I don't get the correct answer, it will be good practice to put what I know into practice. This is my weakness, which I keep coming back to - that when some problem solving is required, I fold far too quickly. So here is what I need to do: Let's break this down... I need to use the...
Read more

Angela Yu Xcode 12 Course - Part 7 (lectures 74 to 79)

Image
No time to waste! Only got a short amount of time now so going to get a few minutes or so in! Start Time - 20:14 Conditionals If statement for 'love calculator' example. So a simple example for this. The idea will be that conditionals are used to show that the print statement will do it differently for whatever the number is. With updated Swift, I would use the Int.random(0...100). Easy fix that would be. Also no UIInt32 needed but just an Int. So with the if statements, it would be a STRING being returned.   Linked to the whole choose your own adventure - if/else for each choice. BMI Challenge No need to do this - easy enough to be honest. Just skimming through. BODMAS principles... So something I picked up on before is not needing the greater than AND less than value for the middle line (for the else if bmi > 18.5) A better solution, which Angela is already explaining before I could say it is returning a string instead of a Double. So the...
Read more