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| 'use strict'
var React = require('react'); var PropTypes = require('prop-types'); var ReactDOM = require('react-dom'); var qr = require('qr.js');
function getBackingStorePixelRatio(ctx) { return ( ctx.webkitBackingStorePixelRatio || ctx.mozBackingStorePixelRatio || ctx.msBackingStorePixelRatio || ctx.oBackingStorePixelRatio || ctx.backingStorePixelRatio || 1 ); }
var getDOMNode; if (/^0\.14/.test(React.version)) { getDOMNode = function(ref) { return ref; } } else { getDOMNode = function(ref) { return ReactDOM.findDOMNode(ref); } }
class QRCode extends React.Component { shouldComponentUpdate(nextProps) { var that = this; return Object.keys(QRCode.propTypes).some(function(k) { return that.props[k] !== nextProps[k]; }); }
componentDidMount() { this.update(); }
componentDidUpdate() { this.update(); }
utf16to8(str) { var out, i, len, c; out = ""; len = str.length; for (i = 0; i < len; i++) { c = str.charCodeAt(i); if ((c >= 0x0001) && (c <= 0x007F)) { out += str.charAt(i); } else if (c > 0x07FF) { out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F)); out += String.fromCharCode(0x80 | ((c >> 6) & 0x3F)); out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F)); } else { out += String.fromCharCode(0xC0 | ((c >> 6) & 0x1F)); out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F)); } } return out; }
update() { var value = this.utf16to8(this.props.value); var qrcode = qr(value); var canvas = getDOMNode(this.refs.canvas);
var ctx = canvas.getContext('2d'); var cells = qrcode.modules; var tileW = this.props.size / cells.length; var tileH = this.props.size / cells.length; var scale = (window.devicePixelRatio || 1) / getBackingStorePixelRatio(ctx); canvas.height = canvas.width = this.props.size * scale; ctx.scale(scale, scale);
cells.forEach(function(row, rdx) { row.forEach(function(cell, cdx) { ctx.fillStyle = cell ? this.props.fgColor : this.props.bgColor; var w = (Math.ceil((cdx + 1) * tileW) - Math.floor(cdx * tileW)); var h = (Math.ceil((rdx + 1) * tileH) - Math.floor(rdx * tileH)); ctx.fillRect(Math.round(cdx * tileW), Math.round(rdx * tileH), w, h); }, this); }, this);
if (this.props.logo) { var self = this var size = this.props.size; var image = document.createElement('img'); image.src = this.props.logo; image.onload = function() { var dwidth = self.props.logoWidth || size * 0.2; var dheight = self.props.logoHeight || image.height / image.width * dwidth; var dx = (size - dwidth) / 2; var dy = (size - dheight) / 2; image.width = dwidth; image.height = dheight; console.log('dwidth', dwidth) console.log('dheight', dheight) ctx.drawImage(image, dx, dy, dwidth, dheight); } } if (this.props.onCanvasLoad){ this.props.onCanvasLoad(canvas.toDataURL('image/png')) } }
render() { return React.createElement('canvas', { style: { height: this.props.size, width: this.props.size }, height: this.props.size, width: this.props.size, ref: 'canvas', }); } }
QRCode.propTypes = { value: PropTypes.string.isRequired, size: PropTypes.number, bgColor: PropTypes.string, fgColor: PropTypes.string, logo: PropTypes.string, logoWidth: PropTypes.number, logoHeight: PropTypes.number, onCanvasLoad: PropTypes.func, };
QRCode.defaultProps = { size: 128, bgColor: '#FFFFFF', fgColor: '#000000', value: 'http://facebook.github.io/react/' };
module.exports = QRCode;
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