Reputation: 745
Hi I'm new to React and Hooks like useState. I'm having a hard time grasping the concept and how to use it. So I don't want to make more complex pieces and files than I have too.
I've run into a problem switching a React.component from a function to a class, Popover.
I've forked off a CodeSandbox to try to show what I'd like to switch too. But, I just can't understand the documentation well enough to make it happen.
What needs to happen to have a React.Class.Component use React-States?
<Button aria-describedby={id} variant="contained" onClick={handleClick}>
Open Popover
</Button>
<Popover
id={id}
open={open}
anchorEl={anchorEl}
onClose={handleClose}
anchorOrigin={{
vertical: 'bottom',
horizontal: 'left',
}}
>
<Typography sx={{ p: 2 }}>The content of the Popover.</Typography>
</Popover>
Upvotes: 0
Views: 2664
Reputation: 172
import React, { Component } from "react";
import { makeStyles } from "@material-ui/core/styles";
import Popover from "@material-ui/core/Popover";
import Typography from "@material-ui/core/Typography";
import Button from "@material-ui/core/Button";
// const useStyles = makeStyles(theme => ({
// typography: {
// padding: theme.spacing(2)
// }
// }));
export default class SimplePopover extends Component {
constructor(props) {
super(props);
// const classes = useStyles();
// const [anchorEl, setAnchorEl] = React.useState(null);
this.state = {
anchorEl: null,
open: false,
id: undefined
}
this.handleClick = this.handleClick.bind(this);
this.handleClose = this.handleClose.bind(this);
// const open = Boolean(anchorEl);
// const id = open ? "simple-popover" : undefined;
}
handleClick(event) {
this.setState({anchorEl: event.currentTarget, open: Boolean(event.currentTarget), id: "simple-popover"});
}
handleClose(event) {
this.setState({anchorEl: event.currentTarget, open: false, id: undefined});
}
render() {
return (
<div>
<Button
aria-describedby={this.id}
variant="contained"
color="primary"
onClick={this.handleClick}
>
Open Popover
</Button>
<Popover
id={this.id}
open={this.state.open}
anchorEl={this.state.anchorEl}
onClose={this.handleClose}
anchorOrigin={{
vertical: "bottom",
horizontal: "center"
}}
transformOrigin={{
vertical: "top",
horizontal: "center"
}}
>
{/* <Typography className={this.classes.typography}> */}
<div>The content of the Popover.</div>
{/* </Typography> */}
</Popover>
</div>
);
}
}
Mistake
const [anchorEl, setAnchorEl] = React.useState(null);
You cannot use a Hook inside a class Component
Upvotes: 3