donphan/app/javascript/mastodon/features/ui/components/image_loader.js

68 lines
1.3 KiB
JavaScript

import React from 'react';
import PropTypes from 'prop-types';
export default class ImageLoader extends React.PureComponent {
static propTypes = {
alt: PropTypes.string,
src: PropTypes.string.isRequired,
previewSrc: PropTypes.string.isRequired,
width: PropTypes.number.isRequired,
height: PropTypes.number.isRequired,
}
static defaultProps = {
alt: '',
};
state = {
loading: true,
error: false,
}
componentWillMount() {
this._loadImage(this.props.src);
}
componentWillReceiveProps(props) {
this._loadImage(props.src);
}
_loadImage(src) {
const image = new Image();
image.onerror = () => this.setState({ loading: false, error: true });
image.onload = () => this.setState({ loading: false, error: false });
image.src = src;
this.setState({ loading: true });
}
render() {
const { alt, src, previewSrc, width, height } = this.props;
const { loading } = this.state;
return (
<div className='image-loader'>
<img
alt={alt}
className='image-loader__img'
src={src}
width={width}
height={height}
/>
{loading &&
<img
alt=''
src={previewSrc}
className='image-loader__preview-img'
/>
}
</div>
);
}
}