Another way to do it that will render a preview image (the below example uses React 16+ syntax and only accepts a single image file to send to an API; however, with some minor tweaks, it can also scale to multiple images and other fields inputs):
Working example: https://codesandbox.io/s/m58q8l054x
Working example (outdated): https://codesandbox.io/s/8kywn8q9xl
Before:
After:
containers/UploadForm.js
import React, { Component } from "react";
import { Form, Field, reduxForm } from "redux-form";
import DropZoneField from "../components/dropzoneField";
const imageIsRequired = value => (!value ? "Required" : undefined);
class UploadImageForm extends Component {
state = { imageFile: [] };
handleFormSubmit = formProps => {
const fd = new FormData();
fd.append("imageFile", formProps.imageToUpload.file);
// append any additional Redux form fields
// create an AJAX request here with the created formData
alert(JSON.stringify(formProps, null, 4));
};
handleOnDrop = (newImageFile, onChange) => {
const imageFile = {
file: newImageFile[0],
name: newImageFile[0].name,
preview: URL.createObjectURL(newImageFile[0]),
size: newImageFile[0].size
};
this.setState({ imageFile: [imageFile] }, () => onChange(imageFile));
};
resetForm = () => this.setState({ imageFile: [] }, () => this.props.reset());
render = () => (
<div className="app-container">
<h1 className="title">Upload An Image</h1>
<hr />
<Form onSubmit={this.props.handleSubmit(this.handleFormSubmit)}>
<Field
name="imageToUpload"
component={DropZoneField}
type="file"
imagefile={this.state.imageFile}
handleOnDrop={this.handleOnDrop}
validate={[imageIsRequired]}
/>
<button
type="submit"
className="uk-button uk-button-primary uk-button-large"
disabled={this.props.submitting}
>
Submit
</button>
<button
type="button"
className="uk-button uk-button-default uk-button-large"
disabled={this.props.pristine || this.props.submitting}
onClick={this.resetForm}
style={{ float: "right" }}
>
Clear
</button>
</Form>
<div className="clear" />
</div>
);
}
export default reduxForm({ form: "UploadImageForm" })(UploadImageForm);
components/dropzoneField.js
import React from "react";
import PropTypes from "prop-types";
import DropZone from "react-dropzone";
import ImagePreview from "./imagePreview";
import Placeholder from "./placeholder";
import ShowError from "./showError";
const DropZoneField = ({
handleOnDrop,
input: { onChange },
imagefile,
meta: { error, touched }
}) => (
<div className="preview-container">
<DropZone
accept="image/jpeg, image/png, image/gif, image/bmp"
className="upload-container"
onDrop={file => handleOnDrop(file, onChange)}
>
{({ getRootProps, getInputProps }) =>
imagefile && imagefile.length > 0 ? (
<ImagePreview imagefile={imagefile} />
) : (
<Placeholder
error={error}
touched={touched}
getInputProps={getInputProps}
getRootProps={getRootProps}
/>
)
}
</DropZone>
<ShowError error={error} touched={touched} />
</div>
);
DropZoneField.propTypes = {
error: PropTypes.string,
handleOnDrop: PropTypes.func.isRequired,
imagefile: PropTypes.arrayOf(
PropTypes.shape({
file: PropTypes.file,
name: PropTypes.string,
preview: PropTypes.string,
size: PropTypes.number
})
),
label: PropTypes.string,
onChange: PropTypes.func,
touched: PropTypes.bool
};
export default DropZoneField;
components/imagePreview.js
import React from "react";
import PropTypes from "prop-types";
const ImagePreview = ({ imagefile }) =>
imagefile.map(({ name, preview, size }) => (
<div key={name} className="render-preview">
<div className="image-container">
<img src={preview} alt={name} />
</div>
<div className="details">
{name} - {(size / 1024000).toFixed(2)}MB
</div>
</div>
));
ImagePreview.propTypes = {
imagefile: PropTypes.arrayOf(
PropTypes.shape({
file: PropTypes.file,
name: PropTypes.string,
preview: PropTypes.string,
size: PropTypes.number
})
)
};
export default ImagePreview;
components/placeholder.js
import React from "react";
import PropTypes from "prop-types";
import { MdCloudUpload } from "react-icons/md";
const Placeholder = ({ getInputProps, getRootProps, error, touched }) => (
<div
{...getRootProps()}
className={`placeholder-preview ${error && touched ? "has-error" : ""}`}
>
<input {...getInputProps()} />
<MdCloudUpload style={{ fontSize: 100, paddingTop: 85 }} />
<p>Click or drag image file to this area to upload.</p>
</div>
);
Placeholder.propTypes = {
error: PropTypes.string,
getInputProps: PropTypes.func.isRequired,
getRootProps: PropTypes.func.isRequired,
touched: PropTypes.bool
};
export default Placeholder;
components/showError.js
import React from "react";
import PropTypes from "prop-types";
import { MdInfoOutline } from "react-icons/md";
const ShowError = ({ error, touched }) =>
touched && error ? (
<div className="error">
<MdInfoOutline
style={{ position: "relative", top: -2, marginRight: 2 }}
/>
{error}
</div>
) : null;
ShowError.propTypes = {
error: PropTypes.string,
touched: PropTypes.bool
};
export default ShowError;
styles.css
img {
max-height: 240px;
margin: 0 auto;
}
.app-container {
width: 500px;
margin: 30px auto;
}
.clear {
clear: both;
}
.details,
.title {
text-align: center;
}
.error {
margin-top: 4px;
color: red;
}
.has-error {
border: 1px dotted red;
}
.image-container {
align-items: center;
display: flex;
width: 85%;
height: 80%;
float: left;
margin: 15px 10px 10px 37px;
text-align: center;
}
.preview-container {
height: 335px;
width: 100%;
margin-bottom: 40px;
}
.placeholder-preview,
.render-preview {
text-align: center;
background-color: #efebeb;
height: 100%;
width: 100%;
border-radius: 5px;
}
.upload-container {
cursor: pointer;
height: 300px;
}