reservation-uniapp-250509/service-uniapp-client/components/placard.vue

<template>
	<view class="placard">
		<view class="placard-content">
			<view class="img-box" :style="{ width: canvasW + 'px', height: canvasH + 'px' }">
				<img v-show="tempFilePath" :style="{ width: canvasW + 'px', height: canvasH + 'px' }" :src="tempFilePath" alt="" />
			</view>
			<div class="qrcode" style="display: none;">
				<vue-qrcode :value="qrCodeValue" :width="qrCodeSize"
					:color="{ dark: qrCodeDarkColor, light: qrCodeLightColor }" :margin="margin"
					type="image/png"></vue-qrcode>
			</div>
			<canvas :style="{ width: canvasW + 'px', height: canvasH + 'px' }"
				canvas-id="myCanvas" id="myCanvas"></canvas>
				
			<view class="add-btn">
				<view class="btn">
					长按图片保存到手机
				</view>
			</view>
		</view>
	</view>
</template>

<script>
	import drawTextVertical from '@/utils/Canvas.js'
	import VueQrcode from 'vue-qrcode'
	export default {
		name: 'Placard',
		components : { VueQrcode },
		data() {
			return {
				qrCodeValue: import.meta.env.VITE_REDIRECT_URI + `?vid=${this.getUserInfo()}`,
				qrCodeSize: 180 * (window.innerWidth / 750),
				qrCodeDarkColor: '#000',
				qrCodeLightColor: '#fff',
				margin: 0,

				//画布信息
				canvasW: 299,
				canvasH: 403,

				//设备信息
				systemInfo: {},

				//图片路径
				tempFilePath: '',

				_rpx: 0,
				_center: 0
			}
		},
		methods: {
			async draw() { //绘制海报
				let self = this
				//获取设备信息
				self.systemInfo = await self.getSystemInfo();
				//转换相对单位
				let rpx = self.systemInfo.windowWidth / 750
				self._rpx = rpx
				//设置画布宽高
				self.canvasW = 542 * rpx
				self.canvasH = 731 * rpx

				//海报背景
				let bg = new Image();
				bg.src = import.meta.env.VITE_REDIRECT_URI + '/static/placard/placard-bg.png'
				//logo
				let logo = new Image();
				logo.src = import.meta.env.VITE_REDIRECT_URI + '/static/placard/logo.png'

				bg.onload = () => {
					logo.onload = () => {		//确保背景和logo加载完成(不然海报可能会少logo)
						setTimeout(() => {
							let ctx = document.querySelector('canvas').getContext('2d')
							let img = document.querySelector('.qrcode img')
						
							let center = self.canvasW / 2; //画布中心位置
							self._center = center
						
							//绘制图片
							ctx.drawImage(bg, 0, 0, self.canvasW, self.canvasH)
							ctx.drawImage(img, center - (self.qrCodeSize / 2), 295 * rpx, self.qrCodeSize, self
								.qrCodeSize)
							ctx.drawImage(logo, center - (100 * rpx / 2) , 60 * rpx , 100 * rpx, 100 * rpx)
						
							//绘制文字
							ctx.font = `bold ${40 * rpx}px 楷体`
							ctx.textAlign = 'center'
							ctx.fillStyle = "#59B495";
							ctx.fillText('上门服务', center, 200 * rpx, 400)
						
							ctx.fillStyle = "#0A543B";
							ctx.font = `100 ${25 * rpx}px 楷体`
							ctx.fillText(`一扫疲劳 舒服入眠`, center, 240 * rpx, 400)
						
							ctx.font = `100 ${25 * rpx}px 宋体`
							ctx.fillStyle = "#0A543B";
							ctx.textAlign = 'center';
							drawTextVertical(ctx, '微信扫码下单', 130 * rpx, 315 * rpx, self.qrCodeSize);
						
							ctx.textAlign = 'center';
							drawTextVertical(ctx, '在线选择技师', 400 * rpx, 315 * rpx, self.qrCodeSize);
						
							ctx.font = `100 ${18 * rpx}px 宋体`
							ctx.fillStyle = '#053323'
							ctx.fillText(`长按扫一扫下单可领取`, center, 525 * rpx, 400)
						
							ctx.font = `bold ${43 * rpx}px 宋体`
							ctx.fillStyle = '#EC8D44'
							ctx.fillText(`200元`, center, 580 * rpx, 400)
						
							ctx.font = `100 ${18 * rpx}px 宋体`
							ctx.fillText(`百万明星技师在线接单`, center, 625 * rpx, 400)
						
							//画图形
							this.paintingCapsule(ctx, center - (90 * rpx / 2), 250 * rpx, 90 * rpx, 25 * rpx,
								13 * rpx, '#59B495', 'time')
							this.paintingCapsule(ctx, center + (130 * rpx / 2), 530 * rpx, 25 * rpx, 70 * rpx,
								13 * rpx, '#BCEED6', 'coupon')
						
							////画海报最后的标签列表
							this.drawList(ctx, 135 * rpx, 650 * rpx, 60 * rpx, 20 * rpx, 10 * rpx, '#59B495')
						
							uni.canvasToTempFilePath({
								x: 0, // 起点坐标
								y: 0,
								width: self.canvasW, // canvas 宽
								height: self.canvasH, // canvas 高
								canvasId: 'myCanvas', // canvas id
								success(res) {
									self.tempFilePath = res.tempFilePath //相对路径
								}
							})
						})
					}
				}
			},
			// 获取设备信息
			getSystemInfo() {
				return new Promise((req, rej) => {
					uni.getSystemInfo({
						success: function(res) {
							req(res)
						}
					});
				})
			},
			paintingCapsule(ctx, x, y, width, height, radius, color, current) { //画椭圆(胶囊)
				// 开始新的路径
				ctx.beginPath();
				// 绘制左上角圆角  
				ctx.moveTo(x + radius, y);
				ctx.arcTo(x + width, y, x + width, y + height, radius);
				// 绘制右上角圆角  
				ctx.arcTo(x + width, y + height, x, y + height, radius);
				// 绘制右下角圆角  
				ctx.arcTo(x, y + height, x, y, radius);
				// 绘制左下角圆角  
				ctx.arcTo(x, y, x + width, y, radius);
				// 闭合路径（实际上在arcTo后已经是闭合的，但显式调用可以增加可读性）  
				ctx.closePath();
				// 设置填充颜色  
				ctx.fillStyle = color;
				// 填充路径  
				ctx.fill();

				//下面是再写不同区域的内容
				if (current == 'time') {
					ctx.fillStyle = "#fff";
					ctx.font = `100 ${17 * this._rpx}px 楷体`
					ctx.fillText(`24小时`, this._center, 267 * this._rpx);
				} else if (current == 'coupon') {
					ctx.fillStyle = "#EC8D44";
					ctx.font = `100 ${13 * this._rpx}px 楷体`
					let offset = 13 * this._rpx
					drawTextVertical(ctx, '优惠券', 349 * this._rpx, 555 * this._rpx, height - offset);
				}
			},
			drawList(ctx, x, y, width, height, radius, color) { //画海报最后的标签列表
				let list = ['安全', '正规', '健康', '便捷']
				let offset = 15 //偏移量
				let currentTagInfo = {
					x
				}

				list.forEach(item => {
					// 开始新的路径
					ctx.beginPath();
					// 绘制左上角圆角  
					ctx.moveTo(currentTagInfo.x + radius, y);
					ctx.arcTo(currentTagInfo.x + width, y, currentTagInfo.x + width, y + height, radius);
					// 绘制右上角圆角  
					ctx.arcTo(currentTagInfo.x + width, y + height, currentTagInfo.x, y + height, radius);
					// 绘制右下角圆角  
					ctx.arcTo(currentTagInfo.x, y + height, currentTagInfo.x, y, radius);
					// 绘制左下角圆角  
					ctx.arcTo(currentTagInfo.x, y, currentTagInfo.x + width, y, radius);
					// 设置边框颜色  
					ctx.strokeStyle = color;
					// 设置边框宽度（可选）  
					ctx.lineWidth = 1; // 或者你想要的任何宽度 
					// 闭合路径（实际上在arcTo后已经是闭合的，但显式调用可以增加可读性）
					ctx.closePath();
					// 绘制边框
					ctx.stroke();
					
					//圆点
					ctx.beginPath();
					ctx.fillStyle = color;
					ctx.arc(currentTagInfo.x + (10 * this._rpx), y + (10 * this._rpx), 2, 0,360)
					ctx.fill()
					
					//绘制文本
					ctx.font = `100 ${13 * this._rpx}px 楷体`
					ctx.fillText(item, currentTagInfo.x + (33 * this._rpx), y + (15 * this._rpx), 400)
					
					let next = currentTagInfo.x + width + offset;		//下一个标签的位置
					currentTagInfo = { x : next }
				})
			},
			getUserInfo(){
				if(localStorage.getItem('userInfo')){
					return JSON.parse(localStorage.getItem('userInfo')).id
				}else{
					uni.navigateTo({
						url: '/pages/login/login'
					})
				}
			}
		}
	}
</script>

<style lang="scss" scoped>
	.placard {
		display: flex;
		min-height: 100vh;
		align-items: center;
		justify-content: center;
		
		.placard-content{
			display: flex;
			flex-direction: column;
			align-items: center;
			
			.add-btn {
				display: flex;
				justify-content: center;
				align-items: center;
				height: 100rpx;
				width: 750rpx;
			
				.btn {
					display: flex;
					align-items: center;
					justify-content: center;
					width: 72%;
					height: 80rpx;
					border-radius: 40rpx;
					color: white;
					font-size: 28rpx;
					background: linear-gradient(180deg, #6FDFBE, #5AC796);
					margin-top: 40rpx;
				}
			}
		}
	}
	
	canvas{
		opacity: 0;
		position: fixed;
		top: 100%;
		left: 0;
	}
</style>