Set <avatar> backgroundColor randomly

Question

I have defined three backgroundColor in the style theme.

avatar: {
    backgroundColor: red[500],
},
orangeAvatar: {
    margin: 10,
    color: '#fff',
    backgroundColor: deepOrange[500],
},
purpleAvatar: {
    margin: 10,
    color: '#fff',
    backgroundColor: deepPurple[500],
}, 

When ever the Avatar is loaded I would like to select one of them randomly.

<Card>
            <CardHeader
                avatar={
                    <Avatar id="av" aria-label="Recipe"
                        className={classes.avatar}>{this.props.userName.charAt(0).toLocaleUpperCase()}
                    </Avatar>}
                title={this.props.userName} disableTypography={true}/>
            <CardActionArea disabled={this.state.images.length == 1 ? true : false}>
                <CardMedia
                    id={this.props.ownerId}
                    className={classes.media}
                    image={this.state.images[this.state.imageIndex]}
                    onClick={this.handleOnClick}
                />
            </CardActionArea>
        </Card>

Any advice how to do this?

Thank you

Answer 1

Several ways to do what you want. My suggestion: put the 3 classes in an array, pick a random number between 0 and 2 every time, and assign that class name:

<Avatar className={classes[Math.floor(Math.random() * 3)]}.../>

Answer 2

let classNameHolder = ["avatar","orangeAvatar","purpleAvatar"];
<Card>
            <CardHeader
                avatar={
                    <Avatar id="av" aria-label="Recipe"
                        className={classNameHolder[Math.floor(Math.random() * 3)]}>{this.props.userName.charAt(0).toLocaleUpperCase()}
                    </Avatar>}
                title={this.props.userName} disableTypography={true}/>
            <CardActionArea disabled={this.state.images.length == 1 ? true : false}>
                <CardMedia
                    id={this.props.ownerId}
                    className={classes.media}
                    image={this.state.images[this.state.imageIndex]}
                    onClick={this.handleOnClick}
                />
            </CardActionArea>
        </Card>

Answer 3

我也面临同样的需要，也许这种解决方案也可以为您服务，这里有一个函数可以随机生成颜色，然后从在线样式中调用该函数。

const useStyles = makeStyles((theme: Theme) =>
  createStyles({
    large: {
      fontSize: "2.5rem",
      width: 100,
      height: 100
    }
  })
);

function randomColor() {
  let hex = Math.floor(Math.random() * 0xFFFFFF);
  let color = "#" + hex.toString(16);

  return color;
}

...

  return (
    <Avatar
      variant="square"
      src={imageSrc}
      alt={alt}
      className={classes.large}
      style={{
        backgroundColor: randomColor()
      }}
    />
  )

参考：

Javascript random color

Avatar random backgroundColor on fallback