As I am currently learning React, I am creating a joke generator. I created a local file and was able to pull the data (jokes) and display it on the browser. Now, I am trying to create a button that when you click, it displays a random joke. I can see the joke and button, but no action is being triggered. I check the console and there are no errors. If I use onClick = {randomJoke}
, then I get an error saying listener was expecting a function, not an object. Can someone point help me out and point out what is wrong?
This is how I currently have it set up:
import React from 'react'
import SportsJokesData from './SportsJokesData';
class SportsJokesApi extends React.Component {
constructor(props){
super(props);
this.getRandomJoke = this.getRandomJoke.bind(this);
}
getRandomJoke(){
return SportsJokesData[(SportsJokesData.length * Math.random()) << 0]
}
render() {
const randomJoke = this.getRandomJoke()
return (
<React.Fragment>
<p> {randomJoke.question}</p>
<p>{randomJoke.answer}</p>
<button onClick={this.getRandomJoke}>
click here
</button>
</React.Fragment>
)
}
}
export default SportsJokesApi;
This is how the file was originally scripted prior to adding the button.
import React from 'react'
import SportsJokesData from './SportsJokesData';
class SportsJokesApi extends React.Component {
getRandomJoke(){
return SportsJokesData[(SportsJokesData.length * Math.random()) << 0]
}
render() {
const randomJoke = this.getRandomJoke()
return (
<React.Fragment>
<p>{randomJoke.question}</p>
<h1>{randomJoke.answer}</h1>
</React.Fragment>
)
}
}
export default SportsJokesApi;
You cannot just return
a new component on onClick
event. You need to set some state first. This guide is useful: https://flaviocopes.com/react-show-different-component-on-click/
You need to re-render your React component, when there is a new joke. To do this store the randomJoke
in the state
of your React Component.
When you call this.getRandomJoke
you should update the state
along with it, so that a re-render of the React component is triggered. When this happens the UI will be updated with the latest value of the randomJoke
import React from 'react' import SportsJokesData from './SportsJokesData'; const initialState = { randomJoke: null }; class SportsJokesApi extends React.Component { constructor(props) { super(props); this.getRandomJoke = this.getRandomJoke.bind(this); this.state = initialState; } getRandomJoke() { this.setState({ randomJoke: SportsJokesData[(SportsJokesData.length * Math.random()) << 0] }); } render() { const { randomJoke } = this.state; return ( <React.Fragment > <p> {randomJoke.question} </p> <p> {randomJoke.answer} </p> <button onClick = {this.getRandomJoke}>click here </button> </React.Fragment > ); } } export default SportsJokesApi;
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.