pad-app/pages/shipWork/sign.vue

<template>
	<view class="sign">
		<head-view title="单证签名" :url="backUrl"></head-view>
		<view class="container contentFixed">
			<view class="sign-box">
				<canvas class="mycanvas" :style="{width:width +'px',height:height +'px'}" canvas-id="mycanvas"
					@touchstart="touchstart" @touchmove="touchmove" @touchend="touchend"></canvas>
				<canvas canvas-id="camCacnvs" :style="{width:height +'px',height:width +'px'}"
					class="canvsborder"></canvas>
			</view>
			<view class="sigh-btns">
				<view class="btn qx" @click="handleCancel">取消</view>
				<view class="btn qc" @click="handleReset">清除</view>
				<view class="btn bc" @click="handleConfirm">保存</view>
			</view>
		</view>
	</view>
</template>
<script>
	import {
		pathToBase64,
		base64ToPath
	} from '../../js_sdk/mmmm-image-tools/index.js'
	import {
		compressImgBySize
	} from '@/common/compressImg'
	import sqlite from "../../common/sqlite.js"
	import api from "../../common/api.js"
	import {
		v4 as uuidv4
	} from 'uuid';
	var x = 20;
	var y = 20;
	var tempPoint = []; //用来存放当前画纸上的轨迹点
	var id = 0;
	var type = '';
	let that;
	let canvasw;
	let canvash;
	export default {
		data() {
			return {
				ctx: '', //绘图图像
				points: [], //路径点集合,
				width: 0,
				height: 0,
				sginId: "",
				signImgUrl: "",
				nextUrl: "",
				signType: "",
				signTable: "",
				backUrl: "",
				tabsValue: 0,
				vvyId: "",
			};
		},
		onLoad(option) {
			this.sginId = JSON.parse(decodeURIComponent(option.params)).id
			this.nextUrl = JSON.parse(decodeURIComponent(option.params)).url
			this.signType = JSON.parse(decodeURIComponent(option.params)).signType
			this.signTable = JSON.parse(decodeURIComponent(option.params)).signTable
			this.tabsValue = JSON.parse(decodeURIComponent(option.params)).tabsValue
			this.vvyId = JSON.parse(decodeURIComponent(option.params)).vvyId
			this.backUrl = `/pages/shipWork/${this.nextUrl}`
			this.vtpId = uni.getStorageSync('vtpId')
			that = this;
			id = option.id;
			type = option.type;
			this.ctx = uni.createCanvasContext('mycanvas', this); //创建绘图对象
			//设置画笔样式
			this.ctx.lineWidth = 4;
			this.ctx.lineCap = 'round';
			this.ctx.lineJoin = 'round';

			uni.getSystemInfo({
				success: function(res) {
					that.width = res.windowWidth * 0.8;
					that.height = res.windowHeight * 0.85;
				}
			});
		},
		methods: {
			//触摸开始，获取到起点
			touchstart: function(e) {
				let startX = e.changedTouches[0].x;
				let startY = e.changedTouches[0].y;
				let startPoint = {
					X: startX,
					Y: startY
				};

				/* **************************************************
				    #由于uni对canvas的实现有所不同，这里需要把起点存起来
				 * **************************************************/
				this.points.push(startPoint);

				//每次触摸开始，开启新的路径
				this.ctx.beginPath();
			},

			//触摸移动，获取到路径点
			touchmove: function(e) {
				let moveX = e.changedTouches[0].x;
				let moveY = e.changedTouches[0].y;
				let movePoint = {
					X: moveX,
					Y: moveY
				};
				this.points.push(movePoint); //存点
				let len = this.points.length;
				if (len >= 2) {
					this.draw(); //绘制路径
				}
				tempPoint.push(movePoint);
			},

			// 触摸结束，将未绘制的点清空防止对后续路径产生干扰
			touchend: function() {
				this.points = [];
			},

			/* ***********************************************	
			#   绘制笔迹
			#   1.为保证笔迹实时显示，必须在移动的同时绘制笔迹
			#   2.为保证笔迹连续，每次从路径集合中区两个点作为起点（moveTo）和终点(lineTo)
			#   3.将上一次的终点作为下一次绘制的起点（即清除第一个点）
			************************************************ */
			draw: function() {
				let point1 = this.points[0];
				let point2 = this.points[1];
				this.points.shift();
				this.ctx.moveTo(point1.X, point1.Y);
				this.ctx.lineTo(point2.X, point2.Y);
				this.ctx.stroke();
				this.ctx.draw(true);
			},

			handleCancel() {
				uni.navigateBack({
					delta: 1
				});
			},

			//清空画布
			handleReset: function() {
				that.ctx.clearRect(0, 0, that.width, that.height);
				that.ctx.draw(true);
				tempPoint = [];
			},

			//将签名笔迹上传到服务器，并将返回来的地址存到本地
			handleConfirm: function() {
				that = this
				if (tempPoint.length == 0) {
					uni.showToast({
						title: '请先签名',
						icon: 'none',
						duration: 2000
					});
					return;
				} else {
					let signId = that.sginId
					uni.canvasToTempFilePath({
						canvasId: 'mycanvas',
						success: function(res) {
							setTimeout(function() {
								pathToBase64(res.tempFilePath)
									.then(base64 => {
										compressImgBySize(base64, 1200).then(baseImg => {
											// 输出图片base64
											that.signImgUrl = baseImg
											let date = new Date().getTime()
											let webId = uuidv4()
											let webDate = api.getDate(date)
											let sql =
												`insert into workSignTable values('${webId}','${that.vtpId}','${signId}','${that.signImgUrl}','${that.signTable}','${that.signType}','${that.vvyId}','${webDate}')`
											sqlite.executeSqlCeshi(sql).then((
												value) => {
												// 在resolve时执行的回调函数
												let obj = {
													tabsValue: that
														.tabsValue,
												}
												const params =
													encodeURIComponent(JSON
														.stringify(obj));
												uni.navigateTo({
													url: `/pages/shipWork/${that.nextUrl}?params=${params}`
												})
											}).catch((error) => {
												// 在reject时执行的回调函数
												console.error(error);
											});
										})
									})
									.catch(error => {
										console.error(error)
									})
							}, 1000)
						}
					});
				}
			},
		}
	};
</script>

<style lang="scss" scoped>
	page {
		background-color: #fff;
	}

	.container {
		height: calc(100vh - 68px);
		padding-bottom: 30px;
		background-color: #fff;
	}

	.sign-box {
		width: 100%;
		height: 90%;
		margin-left: 10%;
		display: flex;
		flex-direction: column;
		text-align: center;
	}

	.sign-view {
		height: 100%;
	}

	.sigh-btns {
		display: flex;
		justify-content: center;
		width: 100%;
		height: 80px;
		background: #FFFFFF;
		box-shadow: 0 -3px 7px 0 rgba(0, 0, 0, 0.10);
		position: fixed;
		bottom: 0;
	}

	.btn {
		margin: 15.5px 17px;
		width: 200px;
		height: 49px;
		border-radius: 2px;
		font-size: 18px;
		text-align: center;
		line-height: 49px;
	}

	.qx {
		background-color: #eee;
	}

	.qc {
		color: #0067CF;
		background-color: rgba(0, 103, 207, 0.10);
	}

	.bc {
		color: #fff;
		background: #0067CF;
	}


	.mycanvas {
		margin: auto 0rpx;
		background-color: #fbfbfb;
		border: 1px dashed #eee;
	}

	.canvsborder {
		border: 1rpx solid #333;
		position: fixed;
		top: 0;
		left: 10000rpx;
	}
</style>