Javascript - More API Review

Leon Noel

#100Devs

Hand me downs with the patches
Mama put a little money in the mattress
Taught me how to make a silver spoon out of plastic 

Agenda

  • Questions? 

  • Let's Talk -  #100Devs

  • Review - Functions && Loops

  • Review - Arrays

  • Review - Objects

  • Review - Basic APIs

  • Learn - More API work

  • Homework - OOP

Questions

About last class or life

Checking In

Like and Retweet the Tweet

!checkin

You Are Not Alone!

Health First

No Networking Until May

Client Deadline: May 3rd

Client Alternatives

Grassroots Volunteer*

Free Software / Open Source

Codewars !Clan

Clan: #100Devs - leonnoel.com/twitch

Programming

What is a program?

A program is a set of instructions that you write to tell a computer what to do

What is a programming?

Programming is the task of writing those instructions in a language that the computer can understand.

JAVASCRIPT

Loops

What are loops?

Loops

  • Repeat an action some number of times!

  • Three main types of loops in Javascript

  • For, while, and do while loops

  • Each type offers a different way to determine the start and end points of a loop

Loops - For

for (let i = 1; i < 5; i++) {
  console.log(i)
}

Arrays

What are arrays?

Toasters

Arrays

  • A data structure to store ordered collections!

  • Array elements are numbered starting with zero

  • Arrays have many methods to manage the order of elements

  • Can be created by a constructor or literal notation

Declaring Arrays

let newArr = []

Literal Notation

Declaring Arrays

newArr = ['Zebra',true,21]

Arrays are populated with elements

Elements can be of any type

Array Indexing

Array Indexing

newArr = ['Zebra',,true,21]

console.log( newArr[0] )  //Zebra
console.log( newArr[1] )  //undefined
console.log( newArr[2] )  //true
console.log( newArr[3] )  //21

Elements can be accessed by their index numbers

Array Indexing

newArr = ['Zebra',,true,21]

newArr[1] = 'Bob'

console.log( newArr )  

// ['Zebra','Bob',true,21]

Elements can be updated by using the index at that position

Array Length

console.log( newArr.length ) //4

How do you determine how many elements are in your array?

Array Iteration

let bestColors = ['green','blue','yellow','black']

bestColors.forEach((x,i)=> console.log(x))

Iterates through an array passing in the value and index of each element 

Objects

What are objects?

Objects

  • Objects are a collection of variables and functions!

  • Objects represent the attributes and behavior of something used in a program

  • Object variables are called properties and object functions are called methods

  • Objects store "keyed" collections

Think of a physical object

What are it's attributes and behaviors? 

Stopwatch Object

  • Properties (attributes):
    Might contain a variable to represent hours, another to represent minutes, and another to represent seconds. 

 

 

  • Methods (behaviors):
    Might also contain functions that manipulate those values, such as "start ()" and "stop ()".

Stopwatch Object

let stopwatch = {}

stopwatch.currentTime = 12

stopwatch.tellTime = function(time){
  console.log(`The current time is ${time}.`)
}

stopwatch.tellTime(stopwatch.currentTime)

Objects

What if we want to make

a lot of objects?

How much money you got? How many problems you got? How many people done doubted you? Left you out to rot?

Car Factory?

Constructors then Classes

Car Factory

Constructor

function MakeCar(carMake,carModel,carColor,numOfDoors){
  this.make = carMake
  this.model = carModel
  this.color = carColor
  this.doors = numOfDoors
  this.honk = function(){
    alert('BEEP BEEP FUCKER')
  }
  this.lock = function(){
    alert(`Locked ${this.doors} doors!`)
  }
}

let hondaCivic = new MakeCar('Honda','Civic','Silver', 4)

let teslaRoadster = new MakeCar('Tesla','Roadster', 'Red', 2)

Car Factory

We forgot enable bluetooth! 

let teslaRoadster = new MakeCar('Tesla','Roadster', 'Red', 2)

console.log( teslaRoadster.bluetooth )  //undefined

MakeCar.prototype.bluetooth = true

console.log( teslaRoadster.bluetooth ) //true 

A prototype is another object that is used as a fallback source of properties

Car Factory

Why does .toString() work?!?

let teslaRoadster = new MakeCar('Tesla','Roadster', 'Red', 2)

console.log( teslaRoadster.doors.toString() )  // "2" not 2

A prototype is another object that is used as a fallback source of properties

Car Factory

Look Ma! New syntax!

class MakeCar{
  constructor(carMake,carModel,carColor,numOfDoors){
    this.make = carMake
    this.model = carModel
    this.color = carColor
    this.doors = numOfDoors
  }
  honk(){
    alert('BEEP BEEP FUCKER')
  }
  lock(){
    alert(`Locked ${this.doors} doors!`)
  }
}

let hondaCivic = new MakeCar('Honda','Civic','Silver', 4)

let teslaRoadster = new MakeCar('Tesla','Roadster', 'Red', 2)

Classes are like templates for objects!

Let's Code

Objects - Netflix TV Shows

APIs

What are APIs?

APIs

  • A simple interface for some complex action!

  • Think of a restaurant menu! Remember those...

  • Lets one thing communicate with another thing without having to know how things are implemented.

APIs

APIs

Fetch Fido, Fetch!

fetch("https://dog.ceo/api/breeds/image/random")
    .then(res => res.json()) // parse response as JSON
    .then(data => {
      console.log(data)
    })
    .catch(err => {
        console.log(`error ${err}`)
    });

API returns a JSON object that we can use within our apps

APIs

Stop trying to make Fetch happen!

fetch(url)
    .then(res => res.json()) // parse response as JSON
    .then(data => {
      console.log(data)
    })
    .catch(err => {
        console.log(`error ${err}`)
    });

Some APIs need Query Parameters to return the correct data

const url = 'https://www.thecocktaildb.com/api/json/v1/1/search.php?s=margarita'

Let's Code

NASA PHOTOS

Local Storage

Local Storage

Allows you to store data across browser sessions

Put Item Into Local Storage

localStorage.setItem('bestFriend', 'Bob')

Get Item Out Of Local Storage

localStorage.getItem('bestFriend', 'Bob')

Remove Item In Local Storage

localStorage.removeItem('bestFriend', 'Bob')

Remove All In Local Storage

localStorage.clear()

Let's Code

Local botScore Button

Let's Code

A Card Game

Let's Code

A Book Tracker

#100Devs - More API Review

By Leon Noel

#100Devs - More API Review

Class 27 of our Free Web Dev Bootcamp for folx affected by the pandemic. Join live T/Th 6:30pm ET leonnoel.com/twitch and ask questions here: leonnoel.com/discord

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