Learn Swift iOS: Building Lists from Structs Quickly

Alright, let’s talk about this Swift iOS list from struct thing, ya hear? Don’t you go thinkin’ this is gonna be some fancy talk, I’m just gonna tell it like it is, the way I see it. No big words or nothin’.

So, you got this “struct” thing in Swift. It’s like a little box, see? You can put stuff in it. Like, say you got a box for apples. You can put the color in there, like “red,” and the size, like “big.” That’s what a struct does, holds things together. And a “list,” well, that’s just like a grocery list, a whole bunch of things, one after another.

Now, if you wanna make a list of these “struct” boxes in your fancy iPhone app, it ain’t that hard, even for an old gal like me. You gotta tell the app what kind of boxes you got, that’s the “struct” part. Let’s say we’re makin’ a list of animals on the farm. Each animal box, the “struct,” needs a name and a sound. So, our struct looks somethin’ like this:

swift

struct Animal {

var name: String

var sound: String

See? Simple. Name is a word, sound is a word. Now, to make a list, you just tell the app it’s gonna be a list of these animal boxes. It’s like makin’ a shopping list but instead of groceries, it’s animals! You do it somethin’ like this:

swift

var farmAnimals: [Animal] = [

Animal(name: “Cow”, sound: “Moo”),

Animal(name: “Pig”, sound: “Oink”),

Animal(name: “Chicken”, sound: “Cluck”)

There ya go! farmAnimals is your list. See the square brackets? That means list. And inside, you got your animals, each one with a name and a sound, just like we said in that “struct” box thingy.

Now, if you wanna show these animals on your iPhone screen, you gotta go through the list, one by one. It’s like checkin’ off your groceries, see? You go through the list and look at each thing. In fancy talk, they call it “looping,” but it’s just lookin’ through the list, that’s all.

Here’s how you might do it, real simple-like:

swift

for animal in farmAnimals {

print(“The (*) goes (*)”)

See? For each “animal” in that “farmAnimals” list, we print out the name and the sound. Easy peasy. It’ll show “The Cow goes Moo,” then “The Pig goes Oink,” and so on.

And if you wanna add more animals, you just make another “struct” box and stick it in the list. Like, if you got a new sheep, you’d do somethin’ like this:

swift

let newSheep = Animal(name: “Sheep”, sound: “Baa”)

*(newSheep)

Now the sheep is in the list, too. You just “append” it, which is like tackin’ it on at the end. It ain’t rocket science, ya know?

This whole “struct” and “list” thing is just a way to keep things organized. Like my kitchen, I got a place for everything, the spoons go in one drawer, the forks in another. Structs help you keep your stuff organized in your app, and lists let you have a whole bunch of that organized stuff. And that helps your iPhone app run smooth, not all jumbled up like a messy kitchen.

So that’s the gist of it. You make a little “struct” box to hold your stuff, then you make a list of them boxes. And then you can look through the list and do things with the stuff inside. It’s all about keepin’ things tidy, like a good housewife keeps her home. Now, go on and make your fancy iPhone app, and don’t you be tellin’ nobody you learned it from an old woman like me!

And listen, if you want to get real fancy, you can do all sorts of things with these lists. You can sort them, so all the cows are together, and all the pigs are together. You can filter them, so you only see the animals that make loud noises. You can even search them, findin’ just the animal you want. But that’s for another day, this is enough for now. You gotta learn to walk before you can run, ain’t that the truth?

• Remember this: Structs are like little boxes, and lists are like grocery lists.
• Keep your stuff organized, and your app will run better.
• Don’t be afraid to try things, that’s how you learn.

Now, go on, get outta here, and don’t forget what I told ya. And if you get stuck, just remember the spoons go in one drawer, and the forks go in another, keep it organized and you will figure it out!