<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta http-equiv="X-UA-Compatible" content="ie=edge" />
<title></title>
<style type="text/css">
html,
body,
canvas {
padding: 0;
margin: 0;
width: 100%;
height: 100%;
overflow-y: hidden;
background-color: transparent;
}
</style>
</head>
<body>
<canvas id="lime-signature"></canvas>
<script type="text/javascript" src="./uni.webview.1.5.3.js"></script>
<script type="text/javascript" src="./signature.js"></script>
<script>
var signature = null;
var timer = null;
var isStart = false;
var options = null
console.log = function(...args) {
postMessage(args);
};
// function stringify(key, value) {
// if (typeof value === 'object' && value !== null) {
// if (cache.indexOf(value) !== -1) {
// return;
// }
// cache.push(value);
// }
// return value;
// };
function emit(event, data) {
postMessage({
event,
data: typeof data !== "object" && data !== null ? data : JSON.stringify(data),
});
// cache = [];
}
function postMessage(data) {
uni.postMessage({
data
});
}
function update(v = {}) {
if (signature) {
options = v
signature.pen.setOption(v);
} else {
signature = new Signature.Signature({el: "lime-signature"});
canvasEl = signature.canvas.get("el");
options = v
signature.pen.setOption(v)
const width = signature.canvas.get("width");
const height = signature.canvas.get("height");
emit({changeSize: {width,height}})
}
}
function clear() {
signature.clear()
}
function undo() {
signature.undo()
}
function redo() {
signature.redo()
}
function isEmpty() {
const isEmpty = signature.isEmpty()
emit({isEmpty});
}
function isTransparent(color) {
// 判断颜色是否为 transparent
if (color === 'transparent') {
return true;
}
// 判断颜色是否为 rgba 的 a 为 0
if (color.startsWith('rgba')) {
const regex = /\d+(\.\d+)?/g;
const matches = color.match(regex);
if (matches !== null) {
const alpha = parseFloat(matches[3]);
if (alpha === 0) {
return true;
}
}
}
return false;
}
function mask(param){
clearTimeout(timer);
let width = this.signature.canvas.get('width')
let height = this.signature.canvas.get('height')
const canvas = document.createElement('canvas')
const ctx = canvas.getContext('2d');
const pixelRatio = signature.canvas.get('pixelRatio')
let width = signature.canvas.get('width')
let height = signature.canvas.get('height')
canvas.width = width * pixelRatio
canvas.height = height * pixelRatio
this.signature.pen.getMaskedImageData((imageData)=>{
ctx.putImageData(imageData, 0, 0);
const path = canvas.toDataURL();
canvas.remove()
if (typeof path == "string") {
const index = Math.ceil(path.length / 8);
for (var i = 0; i < 8; i++) {
if (i == 7) {
emit({"success": path.substr(i * index, index)});
} else {
emit({"file": path.substr(i * index, index)});
}
}
} else {
console.error("canvas no data");
emit({"fail": "canvas no data"});
}
})
}
function save(param) {
// delete param.success;
// delete param.fail;
clearTimeout(timer);
timer = setTimeout(() => {
let {fileType = 'png', quality = 1, n} = param
const type = `image/${fileType}`.replace(/jpg/, 'jpeg');
const {backgroundColor, landscape, boundingBox} = options
const flag = backgroundColor || landscape || boundingBox
let path = canvasEl.toDataURL(!flag && type, !flag && quality)
if(flag) {
const canvas = document.createElement('canvas')
const pixelRatio = signature.canvas.get('pixelRatio')
let width = signature.canvas.get('width')
let height = signature.canvas.get('height')
let x = 0
let y = 0
const next = () => {
const size = [width, height]
if(landscape) {size.reverse()}
canvas.width = size[0] * pixelRatio
canvas.height = size[1] * pixelRatio
const param = [x, y, width, height, 0 , 0, width, height].map(item => item * pixelRatio)
const context = canvas.getContext('2d')
// context.scale(pixelRatio, pixelRatio)
if (landscape) {
context.translate(0, width * pixelRatio)
context.rotate(-Math.PI / 2)
}
if (backgroundColor && !isTransparent(backgroundColor)) {
context.fillStyle = backgroundColor
context.fillRect(0, 0, width * pixelRatio, height * pixelRatio)
}
// param
context.drawImage(signature.canvas.get('el'), ...param)
path = canvas.toDataURL(type, quality)
canvas.remove()
}
if(boundingBox) {
const res = signature.getContentBoundingBox()
width = res.width
height = res.height
x = res.startX
y = res.startY
next()
} else {
next()
}
}
if (typeof path == "string") {
const index = Math.ceil(path.length / 8);
for (var i = 0; i < 8; i++) {
if (i == 7) {
emit({"success": path.substr(i * index, index)});
} else {
emit({"file": path.substr(i * index, index)});
}
}
} else {
console.error("canvas no data");
emit({"fail": "canvas no data"});
}
}, 30);
}
</script>
</body>
</html>