gas-cylinder-app/pages/order/signatureBoard.vue

<template>
	<view>
		<view class="sign-content">
			<view>
				<view class="reset" @click="backClick" style="position:fixed;bottom: 466rpx;background:#fff;">返回</view>
				<view class="reset" @click="clearClick" style="position:fixed;bottom: 266rpx;background:#fff;">重写</view>
				<view class="reset" @click="saveClick"
					style="position:fixed;bottom: 66rpx;background: #39b54a;color:#fff;">确定</view>
			</view>
			<canvas class="sign" canvas-id="sign" @touchmove="move" @touchstart="start" @touchend="end"
				@touchcancel="cancel" @longtap="tap" disable-scroll="true" @error="error"></canvas>
			<view>
				<view
					style="transform: rotate(90deg);text-align: center;position:fixed;width:130rpx;right:-14rpx;top:46%;">
					签名板</view>
			</view>
		</view>
	</view>
</template>

<script>
	let content = null;
	let touchs = [];

	export default {
		data() {
			return {
				isMove: false,
				createCanvas: false,
				outW: 0,
				outH: 0,
				windowsH: 0,
				windowsW: 0
			};
		},
		onLoad: function(options) {
			this.$nextTick(() => {
				//获得Canvas的上下文
				content = uni.createCanvasContext('sign');
				this.windowsH = uni.getSystemInfoSync().windowHeight;
				this.windowsW = uni.getSystemInfoSync().windowWidth;
				//设置线的颜色
				content.setStrokeStyle('#000000');
				//设置线的宽度
				content.setLineWidth(5);
				//设置线两端端点样式更加圆润
				content.setLineCap('round');
				//设置两条线连接处更加圆润
				content.setLineJoin('round');
				// content.setFillStyle('white')
				// content.fillRect(0, 0, 750, 700)
				// content.draw()
			})
		},
		methods: {
			backClick: function() {
				uni.navigateBack({
					delta: 1
				});
			},
			// 画布的触摸移动开始手势响应
			start: function(event) {
				// console.log("触摸开始" + event.changedTouches[0].x);
				// console.log("触摸开始" + event.changedTouches[0].y);
				//获取触摸开始的 x,y
				let point = {
					x: event.changedTouches[0].x,
					y: event.changedTouches[0].y
				};
				touchs.push(point);
			},
			// 画布的触摸移动手势响应
			move: function(e) {
				let point = {
					x: e.touches[0].x,
					y: e.touches[0].y
				};
				touchs.push(point);
				if (touchs.length >= 2) {
					this.isMove = true;
					this.draw(touchs);
				}
			},
			// 画布的触摸移动结束手势响应
			end: function(e) {
				console.log('触摸结束' + e);
				//清空轨迹数组
				for (let i = 0; i < touchs.length; i++) {
					touchs.pop();
				}
			},
			// 画布的触摸取消响应
			cancel: function(e) {
				console.log('触摸取消' + e);
			},
			// 画布的长按手势响应
			tap: function(e) {
				console.log('长按手势' + e);
			},
			error: function(e) {
				console.log('画布触摸错误' + e);
			},
			//绘制
			draw: function(touchs) {
				let point1 = touchs[0];
				let point2 = touchs[1];
				touchs.shift();
				content.moveTo(point1.x, point1.y);
				content.lineTo(point2.x, point2.y);
				content.stroke();
				content.draw(true);
			},
			//清除操作
			clearClick: function() {
				//清除画布
				content.clearRect(0, 0, this.windowsW, this.windowsH);
				content.draw(true);
				this.isMove = false;
			},
			//保存图片
			saveClick: function() {
				if (this.isMove == false) {
					uni.showToast({
						icon: 'none',
						title: '请绘制签名'
					})
					return
				}
				var that = this;
				uni.showLoading({
					title: '请稍等'
				});
				uni.canvasToTempFilePath({
					canvasId: 'sign',
					success: function(res) {
						uni.getImageInfo({
							src: res.tempFilePath,
							fail() {
								uni.hideLoading();
								uni.showToast({
									title: '获取图片信息失败'
								});
							},
							success: function(image) {
								//要先设置在获取 ，加载问题
								image.height = parseInt(image.height);
								image.width = parseInt(image.width);
								that.outW = image.width;
								that.outH = image.height;
								//修复大屏手机无法生成图片问题
								let maxWidth = that.windowsW - uni.upx2px(240);
								let base = that.outH / that.outW;
								if (that.outH > maxWidth) {
									that.outH = maxWidth;
									that.outW = Math.floor(that.outH / base);
								}
								content.rotate(-Math.PI / 2);
								content.translate(-that.outW, 0);
								content.drawImage(image.path, 0, 0, that.outW, that.outH);
								content.translate(that.outW, 0);
								content.rotate(Math.PI / 2);
								content.draw(false, () => {
									uni.canvasToTempFilePath({
										canvasId: 'sign',
										fileType: 'jpg',
										width: that.outH,
										height: that.outW,
										sdestWidth: image.height,
										sdestHeight: image.width,
										fail(res) {
											uni.hideLoading();
											uni.showToast({
												title: '签名失败',
												icon: 'none'
											});
										},
										success: function(resss) {
											uni.hideLoading();
											that.clearClick()
											uni.$emit('sign', resss
												.tempFilePath);
											uni.navigateBack();
											// let imgArr = [];
											// imgArr.push(resss.tempFilePath);
											// uni.previewImage({
											// 	urls: imgArr,
											// 	success(response) {
											// 		console.log(response);
											// 	}
											// });
										}
									});
								});
							}
						});
					},
					fail() {
						uni.hideLoading();
					}
				});
			}
		}
	};
</script>

<style lang="scss" scoped>
	.sign-content {
		display: flex;
		height: 100vh;
		background: #f1f1f1;
		/*  #ifdef  H5  */
		// height: calc(100vh - 44px);
		/*  #endif  */
		padding: 20rpx 0;
		box-sizing: border-box;

		.reset {
			color: #333;
			background-color: rgb(248, 248, 248);
			border: 1px solid #ddd;
			transform: rotate(90deg);
			margin-top: 20rpx;
			padding: 20rpx 40rpx;
			font-size: 30rpx;
			border-radius: 28rpx;
			border: none;
		}

		.tips {
			width: 600rpx;
			color: red;
			transform: rotate(90deg);
			height: 10px;
			position: fixed;
			left: -233rpx;
			top: 326rpx;
			/*  #ifdef  H5  */
			top: calc(326rpx + 88rpx);
			/*  #endif  */
			font-size: 34rpx;
		}

		.sign {
			flex: 1;
			height: 100%;
			margin-right: 100rpx;
			margin-left: 120rpx;
			border: 1px dashed #ddd;
			background-color: #fff;
		}
	}

	.g-btns {
		text-align: center;
		margin-top: 1rem;
		transform: rotate(90deg);
		-ms-transform: rotate(90deg);
		/* IE 9 */
		-moz-transform: rotate(90deg);
		/* Firefox */
		-webkit-transform: rotate(90deg);
		/* Safari 和 Chrome */
		-o-transform: rotate(90deg);
		position: absolute;
		top: 12rem;
		left: -6rem;
	}

	.g-btns {
		width: 7.5rem;
		height: 2.25rem;
		font-size: 0.9rem;
		font-weight: bold;
		border: none;
		border-radius: 1rem;
	}

	.u-reset {
		background: #ddd;
		color: #666;
		margin-right: 0.5rem;
	}

	.u-submit {
		background: #fc4949;
		color: #fff;
		margin-left: 0.5rem;
	}
</style>