uniapp手写_uniapp+canvas实现手写签字
class="mycanvas"
canvas-id="mycanvas"
@touchstart="touchstart"
@touchmove="touchmove"
@touchend="touchend"
>
确认上传
清除笔迹
import Util from "@/utils/httpUtil.js";
import Local from "@/utils/local.js";
var x = 20;
var y = 20;
export default {
data() {
return {
showCanvas: false,
ctx: "", //绘图图像
points: [], //路径点集合
signature: ""
};
},
mounted() {},
onShow() {
this.createCanvas();
let that = this;
setTimeout(function() {
// 笔迹反显
if (Local.local.getItem("canvasPath")) {
let imgPath = Local.local.getItem("canvasPath");
const sInfo = uni.getSystemInfoSync();
that.ctx.drawImage(
imgPath,
0,
0,
sInfo.windowWidth,
sInfo.windowHeight
);
that.ctx.draw(true);
}
}, 500);
},
methods: {
moveHandle() {},
//关闭并清空画布
close: function() {
this.showCanvas = false;
this.clear();
},
//创建并显示画布
createCanvas: function() {
this.showCanvas = true;
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";
},
//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 };
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
}
},
// 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);
},
//清空画布
clear: function() {
let that = this;
uni.getSystemInfo({
success: function(res) {
let canvasw = res.windowWidth;
let canvash = res.windowHeight;
that.ctx.clearRect(0, 0, canvasw, canvash);
that.ctx.draw(true);
}
});
},
//完成绘画并保存到本地
finish: function() {
let that = this;
uni.canvasToTempFilePath({
canvasId: "mycanvas",
success: function(res) {
console.log(res);
Local.local.setItem("canvasPath", res.tempFilePath);
uni.uploadFile({
url: Util.fileUrl + "/file/objects", //仅为示例，非真实的接口地址
filePath: res.tempFilePath,
name: "file",
header: {
authorization: Local.local.getItem("token")
},
success: uploadFileRes => {
let data = JSON.parse(uploadFileRes.data).data;
console.log(data);
Local.local.setItem("signImg", data.uri);
that.clear();
that.$Common.user.linkBack(1);
}
});
}
});
}
}
};
.signature {
position: fixed;
top: 10px;
left: 2%;
z-index: 999;
width: 96%;
}
page {
background: #fff;
}
.container {
padding: 20rpx 0 120rpx 0;
box-sizing: border-box;
}
.title {
height: 50upx;
line-height: 50upx;
font-size: 16px;
}
.mycanvas {
width: 100%;
height: calc(100vh - 220upx);
background-color: #ececec;
}
.footer {
font-size: 14px;
height: 150upx;
display: flex;
justify-content: space-around;
align-items: center;
}
.left,
.right{
line-height: 100upx;
height: 100upx;
width: 300upx;
text-align: center;
font-weight: bold;
color: white;
border-radius: 5upx;
}
.left {
background: #007aff;
}
.right {
background: orange;
}