This project was bootstrapped with Create React App.
In the project directory, you can run:
Runs the app in the development mode.
Open http://localhost:3000 to view it in the browser.
The page will reload if you make edits.
You will also see any lint errors in the console.
Launches the test runner in the interactive watch mode.
See the section about running tests for more information.
Builds the app for production to the build folder.
It correctly bundles React in production mode and optimizes the build for the best performance.
The build is minified and the filenames include the hashes.
Your app is ready to be deployed!
See the section about deployment for more information.
Note: this is a one-way operation. Once you eject, you can’t go back!
If you aren’t satisfied with the build tool and configuration choices, you can eject at any time. This command will remove the single build dependency from your project.
Instead, it will copy all the configuration files and the transitive dependencies (Webpack, Babel, ESLint, etc) right into your project so you have full control over them. All of the commands except eject will still work, but they will point to the copied scripts so you can tweak them. At this point you’re on your own.
You don’t have to ever use eject. The curated feature set is suitable for small and middle deployments, and you shouldn’t feel obligated to use this feature. However we understand that this tool wouldn’t be useful if you couldn’t customize it when you are ready for it.
A component is a Function or Class that produces HTML to show the user (using JSX) and handles feedback from the user (using event handlers).
- Identify the JSX that appears to be duplicated.
- What is the purpose of that block of JSX? Think of a descriptive name of what it does.
- Create a new file to house this component - it should have the same name as the component.
- Create a new component in the new file, paste the JSX into it.
- Make the component configurable by using React's 'props' system.
- Good for simple content.
- Good for all content
- JS file loaded by browser
- App component gets created
- We call geolocation service
- App returns JSX, gets rendered to page as HTML
- We get result of geolocating
- Tell the component to rerender itself with this new information
- Must be a Javascript class
- Must extend (subclass) React.Component
- Must define a 'render' method that returns some amount of JSX
- {} --> represents JSX interlopation
- Systems for passing data from a parent component to a child component.
- Goal is to customize or configure child component.
- Anytime that we pass a prop to a functional component it is going to show up inside of an object that is the first argument to that functional component.
Structure:
- <CommentDetail author(Name of the prop) = "Sam"(value of the prop) />
- Only usable with class components
- 'State' is a JS object that contains data relevant to a component
- Updating 'State' on a component causes the component to (almost) instantly rerender
- State must be initialized when a component is created.
- State can only be updated using the function 'setState'
- User wants to navigate to another step in the app
- User clicks a 'Link' tag
- React Router prevents the browser from navigating to the new page and fetching new index.html file
- URL still changes
- 'History' object sees updates URL, takes URL and sends it to BrowserRouter
- BrowserRouter communicates the URL to Route components
- Route components rerender to show new set of components
constructor(props) {
super(props);
//this is the only time we do direct assignment to this.state for state object
//this.state is a property
//other then initilizing the state object never do a direct assignment to it
// when we intializing the state object inside the constructor function you can do a direct assignment
this.state = { lat: null, errorMessage: '' };
}- To make sure that the parents React.Components constructor function gets called we call super()
- super() is a reference to parents constructor function
- i.e:
lat > 0 ? 'summer' 'winter' const icon = season === 'winter' ? 'snowflake' : 'sun';
- Constructor - good place to do one time setup
- render (this method is not optional) - avoid doing anything besides returning JSX
- componentDidMount - content visible on screen - good place to do data loading
- componentDidUpdate - sit and wait for updates - good place to do more data loading when state/props change
- componentWillMount - sit and wait until this component is no longer shown - good place to do clean-up (especially for non-react stuff)
componentDidMount() {
console.log('My component was rendered to the screen');
}
componentDidUpdate() {
console.log('My component was just updated - it rendered')
}You can learn more in the Create React App documentation.
To learn React, check out the React documentation.
<iframe
allow="microphone;"
width="350"
height="430"
src="https://console.dialogflow.com/api-client/demo/embedded/50dac474-17b9-4ee4-a46f-603e671b87d0">
</iframe>- Results in a token that a server can use to make requests on behalf of the user
- Usually used when we have an app that needs to access user data when they are not logged in
- Results in a token that a browser app can use to make requests on behalf of the user
- Usually used when we have an app that needs to access user data when they are not logged in
gapi.auth2.getAuthInstance().signOut()
gapi.auth2.getAuthInstance().signOut()
gapi.auth2.getAuthInstance().isSignedIn.get()
gapi.auth2.getAuthInstance().signIn
gapi.auth2.getAuthInstance().signOut()
gapi.auth2.getAuthInstance().signIn()
new Date().getMont()