From e99bca5f49fb389110b41b64601f62438fa2a30d Mon Sep 17 00:00:00 2001 From: kinana52 <93495806+kinana52@users.noreply.github.com> Date: Tue, 8 Feb 2022 01:16:06 -0800 Subject: [PATCH] Delete 003: DOM and Javascript.md --- 003: DOM and Javascript.md | 231 ------------------------------------- 1 file changed, 231 deletions(-) delete mode 100644 003: DOM and Javascript.md diff --git a/003: DOM and Javascript.md b/003: DOM and Javascript.md deleted file mode 100644 index 3285c6d1..00000000 --- a/003: DOM and Javascript.md +++ /dev/null @@ -1,231 +0,0 @@ -# Hack School: Part 3 - DOM Manipulation, React (10/29) - -Slides Link: [here](acmurl.com/hackschool-fa20-pt3) - -Workshop Recording: [here](https://www.youtube.com/channel/UCyjPATFqc3FwOiuqJ2UG1Eg) - - -In the first part of this workshop, we learned about DOM and React. Specifically, we learned **how to access elements using JavaScript and DOM**, **the difference between React and HTML**, **components**, and **props**. - -We used these ideas to to: -- [x] Download React -- [x] Change the style in NavBar -- [x] Create Pokemon.jsx as a React component - - -## What is DOM? - -DOM tree diagram - -DOM is the tree structure that organizes HTML elements. JavaScript uses the DOM organization to access HTML elements--like how you might use an address to find a location. - -The tree structure follows that of any family tree. -- The element directly above is considered a parent (for example, on the far left, the `Element: ` is a parent of `Text: "My title"`). -- The element directly below is considered a child (in the same example, `Text: "My title"` is the child of `Element: <title>`). -- Elements next to one another on the same level are considered siblings (see the bottom right elements `Element: <a>` and `Element: <h1>`). - -In Hack School, we will be using DOM to animate and modify the Pokemon Generator with JavaScript. - -### Selecting by ID or Class - -In the last workshop, we learned how to give HTML elements IDs like this: -``` -<p id = "demo" class = "para">Hello!</p> -``` -Now, using Javascript, we can grab elements and change its different features. - -#### Selecting by ID -``` -document.getElementById(<id_name>).<what_to_grab> -``` -This is the general formula for accessing a webpage element by its *id*. You can see that you select the document as a location; you tell it to search for an element in the document, given an id; and then you can grab and change different properties. - -#### Selecting by Class -``` -document.getElementsByClassName(<id_name>)[index].<what_to_grab> -``` -This is the general formula for accessing a webpage element by its *class*. You can see that you select the document as a location; you tell it to search for an element in the document, given a class. However, since more than one element can be in the same class, we need to specify which element you want to change using the index. - -For example: -``` -<p id = "demo" class = "para">Hello!</p> -<p id = "not_demo" class = "para">Goodbye!</p> -``` -If you want to select the "Goodbye" paragraph, you would input [1] into the index, since Goodbye is the second paragraph and the HTML index starts counting at 0. - -(Which means that in most coding language, "Hello" would be the 0th paragraph and "Goodbye" would be the 1st paragraph.) - -#### `.innerHTML` - -`.innerHTML` is a function that grabs the inner content in between the HTML tags. From there, you can change its innerHTML property. - -For example: -``` -document.getElementById("demo").innerHTML - "Hello World!"; -``` -would change `<p id="demo" class="para">Hello!</p>` to `<p id="demo" class="para">Hello World!</p>` - -#### `.style.color` - -`.style.color` is a function that accesses an element's style description, and then looks specifically for color in that description. From there, you can change an element's color. - -For example: -``` -document.getElementsByClassName("para")[0].style.color = "blue"; -``` -would change `<p id="demo" class="para">Hello!</p>` to blue text. - -## What is React? - -React is a very commonly used front-end framework that has many benefits, including: - -- You can import and re-use components easily -- The webpage only re-renders updated components, so page-rendering is faster -- Don't need to manually update - -React is a javascript framework where you can import external components like CSS and HTML is treated as variable objects, so you can re-use them whenever necessary. - -Note: React uses **className** instead of **class** in HTML. - -#### What are components? -``` -const Example = () => { - return <p> This is a component!</p> -} -``` -Components are code blocks on your websites that do different things. There are two types of components, *functional* and *class*. - -Components are rendered in *return* statements for functional components and the *render()* function for class components. - -You can see above that the example is a functional component because it has `return` in it. If the example didn't have return, it wouldn't render anything; that is, no "This is a component!" paragraph would show up on your webpage. - -#### Functional components - -``` -const MemeSong = (props) => { - return( - <div> - <h1>(props.title)</h1> - <img src={props.coverImg} alt="cover image" /> - <p> Jam to this song with me <a href={props.songLink}>here</a>!</p> - </div> - ); -} -``` - -Functional components are like the first example: -- Follow JavaScript function syntax (look at variable name `const`) and usually written as an arrow function (containing `=>`; for a recap on arrow functions, look at the previous notes) -- Renders JSX (a type of JavaScript language) within a return statement -- Shorter, cleaner code -- Simpler to work with - -We will be using functional components for our project. - -#### Props - -Props are components with features. Here's an example: -``` -<MemeSong -title = "Careless Whispers" -coverImg = "../img/careless-whispers.png" -songLink = "tempurl.com/careless-whispers"/> - -<MemeSong -title = "Take On Me" -coverImg = "../img/take-on-me.png" -songLink = "tempurl.com/take-on-me"/> - -<MemeSong -title= "Nyan Cat" -coverImg = "../img/nyan-cat.png" -songLink = "tempurl.com/nyan-cat" /> -``` - -Each of these <MemeSong> code blocks are called **Components**. Each of the properties (title, coverImg and songLink) are called **Props** (like properties). - -We can access these components and their props by using a React function. - -``` -const MemeSong = (props) => { - return( - <div> - <h1>{props.title}</h1> - <img src={props.coverImg} alt="Cover image" /> - <p>Jam to this song with me - <a href={props.songLink}>here</a>! - </p> - </div> - ); -} -``` - -As you see in the example, we pass `props` as our default argument of the arrow function. The function decides that for each input `props` that it receives, it will access certain props like `props.title` using dot notation. - -This is really helpful because it saves us a lot of time. Instead of writing out all the HTML blocks and inputting the titles, image links and song links individually, we can use props to condense our code! - -## Project Implementation - -### Set up React in your project! - -We'll be using React for our framework, so we should set that up now. - -Use `cd` to move to the directory where your part 1 files are stored on your computer. Then run this command: -``` -npx create-react-app client -``` -Navigate to the client folder, and then the src folder. The file App.js is where our webpage will load from. - -Go into the client folder and run `npm start` to see the webpage. - -### Navbar - -We want to make our navbar for our Pokemon generator. We'll be creating a new .jsx file for it to live in :) - -For that, we use **workshop 1 code** and **functional components**. - -Reference slide 27-31 from the workshop [here](acmurl.com/hackschool-fa20-pt3) - -<details> - <summary> Hint #1: I choose you! </summary> - Did you remember to import React and './style.css'? And did you remember to <code>import</code> each component from <code>.location</code>? Remember, if you don't import, your code won't be able to use it! -</details> - -<details> - <summary> Hint #2: Team Rocket's Blasting Off Again...! </summary> - Did you remember to <code>export default</code> each component? If you don't export them, you can't access them in other files! -</details> - - -### CreatePokemon.jsx - -We want to take our CreatePokemon component, translate it into React, and put it in our src/App.js file for our Pokemon generator. - -For that, we translate HTML to React syntax. - -Reference slide 27-31 from the workshop [here](acmurl.com/hackschool-fa20-pt3) - -Note: -- Change `for` to `htmlFor` -- Change the move power `value` to `defaultValue` - -<details> - <summary> Hint #1: Copy that, Copycat! </summary> - Did you remember to switch all instances of <code>class</code> to <code>className</code>? Remember, we need to do that when switching HTML to React! -</details> - - -## Simple Resources: - -<img src="http://31.media.tumblr.com/tumblr_lr16h9m7YX1qhf88oo1_500.gif" height=50% width=50% alt="Dragonite flying against Team Rocket"> - -Midterm stress got you feeling like you're on a cliff, hopelessly trying to push your deadlines back, and needing a fluffy cat to keep you grounded? Check out our #aww channel on the ACM discord for some fluffy therapy - but hurry back to develop some more React with us! - -Feel free to DM us on Discord if you have any questions or want to arrange some office hours. We're here to help - we promise! :) - -**Main Idea 1**: - -Site #1: [W3 React tutorial](https://www.w3schools.com/react/) - -Note: W3 schools is an ***awesome*** place to learn coding. I would highly recommend it for not only React but also just about any other coding language there is. - -Site #2: [Documentation about DOM from Mozilla](https://developer.mozilla.org/en-US/docs/Web/API/Document_Object_Model/Introduction)