uni-app 使用u-echarts图表插件步骤（圆环）

一、去插件市场下载插件：https://ext.dcloud.net.cn/plugin?id=271

二、把components和static里面的文件复制到自己的项目中

三、使用：

<template>
	<view class="qiun-columns">
		<view class="qiun-charts" >
			<!--#ifdef MP-ALIPAY -->
			<canvas canvas-id="canvasRing" id="canvasRing" class="charts" :style="{'width':cWidth*pixelRatio+'px','height':cHeight*pixelRatio+'px', 'transform': 'scale('+(1/pixelRatio)+')','margin-left':-cWidth*(pixelRatio-1)/2+'px','margin-top':-cHeight*(pixelRatio-1)/2+'px'}" @touchstart="touchRing"></canvas>
			<!--#endif-->
			<!--#ifndef MP-ALIPAY -->
			<canvas canvas-id="canvasRing" id="canvasRing" class="charts" @touchstart="touchRing"></canvas>
			<!--#endif--> 
		</view>
	</view>
</template>

<script>
	import uCharts from '@/components/u-charts/u-charts.js';
	import  { isJSON } from '@/common/checker.js';
	var _self;
	var canvaRing=null;
   
	export default {
		data() {
			return {
				cWidth:'',
				cHeight:'',
				pixelRatio:1,
				textarea:''
			}
		},
		onLoad() {
			_self = this;
			//#ifdef MP-ALIPAY
			uni.getSystemInfo({
				success: function (res) {
					if(res.pixelRatio>1){
						//正常这里给2就行，如果pixelRatio=3性能会降低一点
						//_self.pixelRatio =res.pixelRatio;
						_self.pixelRatio =2;
					}
				}
			});
			//#endif
			this.cWidth=uni.upx2px(750);
			this.cHeight=uni.upx2px(500);
			this.getServerData();
		},
		methods: {
			getServerData(){
				uni.request({
					url: 'https://www.ucharts.cn/data.json',
					data:{
					},
					success: function(res) {
						console.log(res.data.data)
						let Ring={series:[]};
						//这里我后台返回的是数组，所以用等于，如果您后台返回的是单条数据，需要push进去
						Ring.series=res.data.data.Ring.series;
						//自定义文案示例，需设置format字段
						for(let i = 0 ;i < Ring.series.length;i++){
							Ring.series[i].format=()=>{return Ring.series[i].name+Ring.series[i].data};
						}
						_self.textarea = JSON.stringify(res.data.data.Ring);
						_self.showRing("canvasRing",Ring);
					},
					fail: () => {
						_self.tips="网络错误，小程序端请检查合法域名";
					},
				});
			},
			showRing(canvasId,chartData){
				canvaRing=new uCharts({
					$this:_self,
					canvasId: canvasId,
					type: 'ring',
					fontSize:11,
					padding:[5,5,5,5],
					legend:{
						show:true,
						position:'bottom',//解释小点在下方
						float:'center',
						itemGap:10,
						padding:5,
						lineHeight:26,
						margin:5,
						//backgroundColor:'rgba(41,198,90,0.2)',
						//borderColor :'rgba(41,198,90,0.5)',
						borderWidth :1
					},
					background:'#FFFFFF',
					pixelRatio:_self.pixelRatio,
					series: chartData.series,
					animation: false,
					width: _self.cWidth*_self.pixelRatio,
					height: _self.cHeight*_self.pixelRatio,
					disablePieStroke: true,
					dataLabel: true,
					subtitle: {
						name: '70%',
						color: '#7cb5ec',
						fontSize: 25*_self.pixelRatio,
					},
					title: {
						name: '收益率',
						color: '#666666',
						fontSize: 15*_self.pixelRatio,
					},
					extra: {
						pie: {
						  offsetAngle: 0,
						  ringWidth: 40*_self.pixelRatio,
						  labelWidth:15
						}
					},
				});
			},
			// touchRing(e){
			// 	canvaRing.touchLegend(e, {
			// 		animation : false
			// 	});
			// 	canvaRing.showToolTip(e, {
			// 		format: function (item) {
			// 			return item.name + ':' + item.data 
			// 		}
			// 	});
			// },
			// changeData(){
			// 	if(isJSON(_self.textarea)){
			// 		let newdata=JSON.parse(_self.textarea);
			// 		canvaRing.updateData({
			// 			series: newdata.series,
			// 			categories: newdata.categories
			// 		});
			// 	}else{
			// 		uni.showToast({
			// 			title:'数据格式错误'
			// 			// image:'../../../static/images/alert-warning.png'
			// 		})
			// 	}
			// }
		}
	}
</script>

<style>
	/*样式的width和height一定要与定义的cWidth和cHeight相对应*/
	.qiun-charts {
		width: 750upx;
		height: 500upx;
		background-color: #FFFFFF;
	}
	
	.charts {
		width: 750upx;
		height: 500upx;
		background-color: #FFFFFF;
	}
</style>

效果图：