本文实例为大家分享了uniapp实现横屏签字版的具体代码，供大家参考，具体内容如下
兼容H5、APP、微信小程序
可作为组件直接引入
通过this.$emit(‘tempFilePath’, val.tempFilePath)给予回调
<template>
<view class="main-content" v-if="isShow" @touchmove.stop.prevent="">
<!-- 签字canvas -->
<canvas
class="mycanvas"
id="mycanvas"
canvas-id="mycanvas"
@touchstart="touchstart"
@touchmove="touchmove"
@touchend="touchend"
></canvas>
<!-- 旋转canvas -->
<canvas
class="mycanvas"
:style="{ 'z-index': -1, width: `${screenWidth}px`, height: `${(screenWidth * screenWidth) / screenHeight}px` }"
id="rotatCanvas"
canvas-id="rotatCanvas"
></canvas>
<cover-view class="button-line">
<cover-view class="save-button" @tap="finish">保存</cover-view>
<cover-view class="clear-button" @tap="clear">清除</cover-view>
<cover-view class="cancel-button" @tap="hide">关闭</cover-view>
</cover-view>
</view>
</template>
<script>
export default {
data() {
return {
ctx: '', //绘图图像
points: [], //路径点集合
isShow: false,
screenWidth: '',
screenHeight: ''
};
},
mounted() {
this.createCanvas();
uni.getSystemInfo({
success: e => {
this.screenWidth = e.screenWidth;
this.screenHeight = e.screenHeight;
}
});
},
methods: {
show() {
this.clear();
this.isShow = true;
},
hide() {
this.isShow = false;
},
//创建并显示画布
createCanvas() {
this.showCanvas = true;
this.ctx = uni.createCanvasContext('mycanvas', this); //创建绘图对象
//设置画笔样式
this.ctx.lineWidth = 2;
this.ctx.lineCap = 'round';
this.ctx.lineJoin = 'round';
},
//触摸开始，获取到起点
touchstart(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(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() {
this.points = [];
},
draw() {
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() {
this.ctx.clearRect(0, 0, this.screenWidth, this.screenHeight);
this.ctx.draw(true);
},
//完成绘画并保存到本地
finish() {
uni.canvasToTempFilePath(
{
canvasId: 'mycanvas',
success: res => {
this.rotat(res.tempFilePath);
},
complete: com => {}
},
this
);
},
// 将图片选装
rotat(e) {
let rotatCtx = uni.createCanvasContext('rotatCanvas', this); //创建绘图对象
// 重新定位中心点
rotatCtx.translate(0, (this.screenWidth * this.screenWidth) / this.screenHeight);
// 将画布逆时针旋转90度
rotatCtx.rotate((270 * Math.PI) / 180);
// 将签字图片绘制进入Canvas
rotatCtx.drawImage(e, 0, 0, (this.screenWidth * this.screenWidth) / this.screenHeight, this.screenWidth);
// 保存后旋转后的结果
rotatCtx.draw(true);
setTimeout(() => {
// 生成图片并回调
uni.canvasToTempFilePath(
{
canvasId: 'rotatCanvas',
success: val => {
this.$emit('tempFilePath', val.tempFilePath);
setTimeout(() => {
this.hide();
}, 500);
},
complete: com => {
// console.log(com);
}
},
this
);
}, 500);
}
}
};
</script>
<style lang="scss" scoped>
.main-content {
width: 100vw;
height: 100vh;
background-color: red;
position: fixed;
top: 0rpx;
left: 0rpx;
z-index: 9999;
}
.mycanvas {
width: 100vw;
height: 100vh;
background-color: #efefef;
position: fixed;
left: 0rpx;
top: 0rpx;
z-index: 2;
}
.button-line {
transform: rotate(90deg);
position: fixed;
bottom: 170rpx;
left: -100rpx;
width: 340rpx;
height: 50rpx;
display: flex;
align-items: center;
justify-content: space-between;
z-index: 999;
}
.button-style {
color: #ffffff;
width: 100rpx;
height: 60rpx;
text-align: center;
line-height: 60rpx;
border-radius: 10rpx;
}
.save-button {
@extend .button-style;
background-color: #02b340;
}
.clear-button {
@extend .button-style;
background-color: #ffa500;
}
.cancel-button {
@extend .button-style;
background-color: #e10b2b;
}
</style>以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持编程网。
