Angular2使用SVG自定义图表（条形图、折线图）组件示例

本文实例讲述了Angular2使用SVG自定义图表（条形图、折线图）组件。分享给大家供大家参考，具体如下：

要求：用户将数据作为参数传进来，通过类型决定渲染何种类型的图标。

demo：

html:

ts:

 options = {
    type: 'line',   //图表类型
    xAxis: {      //X轴的数据
      data: ['Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat', 'Sun']
    },
    yAxis: {      //X轴的数据
      data: [120, 220, 150, 111, -150, 55, 60],
    },
    width: 600,    //宽
    height: 500,    //高
    dataPadding: 8   //条形图之间的距离
  };

效果：

源代码：

import {
  Input,
  OnInit,
  ViewChild,
  Component,
  ViewEncapsulation,
  ElementRef,
  AfterViewInit,
  ChangeDetectorRef,
} from '@angular/core';
import { NgoChartSvgParams, Scale, Axis, Chart } from './chart-svg-params';
@Component({
  selector: 'ngo-chart-svg',
  templateUrl: './chart-svg.html',
  styleUrls: ['./chart-svg.scss'],
  encapsulation: ViewEncapsulation.Native
})
export class NgoChartSvg implements OnInit, AfterViewInit {
  @Input() inputParams: NgoChartSvgParams;
  @ViewChild('svg') svg: ElementRef;
  @ViewChild('polyline') polyline: ElementRef;
  params: NgoChartSvgParams;
  AxisY: Axis; // Y轴
  AxisX: Axis; // X轴
  valueToPxRatio: number; // 值转px的比率
  Y0: number; // 坐标轴 (0,0)的Y轴
  Yscale: Array = []; // Y轴刻度值
  Xscale: Array = []; // X轴刻度值
  XgapWidth: number; // X轴刻度之间的间隙宽度
  data: Array = [];
  color: string;
  type: string;
  polyLinePoints: string;
  polyLineLength: number;
  constructor(
    private ele: ElementRef,
    private cd: ChangeDetectorRef
  ) { }
  ...
 ngOnInit() {
    this.initParams();
    const svg = this.svg.nativeElement;
    const _width = this.params.width;
    const _height = this.params.height;
    svg.setAttribute('width', _width);
    svg.setAttribute('height', _height);
    // 绘制 y轴
    this.drawAxisY();
    this.drawScaleY();
    // 绘制 x轴
    this.drawAxisX();
    this.drawScaleX();
    this.drawRect();
    if (this.params.type === 'line') {
      this.drawLine();
    }
  }
  ngAfterViewInit() {
    if (this.polyline) {
      this.polyLineLength = this.polyline.nativeElement.getTotalLength();
      this.cd.detectChanges();
    }
  }
}

html

css

svg {
 background: rgba(0, 0, 0, 0.2);
 border: 1px solid black;
}
svg * {
 position: static;
 font-size: 16px;
}
._polyline {
 fill: none;
 animation: lineMove 1.5s ease-in-out forwards;
}
@keyframes lineMove {
 to {
  stroke-dashoffset: 0;
 }
}

一、初始化参数

//首先获取传入的参数
 @Input() inputParams;
//初始化
 const _params: NgoChartSvgParams = {
   xAxis: this.inputParams.xAxis,
   yAxis: this.inputParams.yAxis,
   type: this.inputParams.type ? this.inputParams.type : 'bar',
   width: this.inputParams.width ? this.inputParams.width : 700,
   height: this.inputParams.height ? this.inputParams.height : 500,
   dataPadding: this.inputParams.dataPadding !== undefined ? this.inputParams.dataPadding : 8,
   YscaleNo: this.inputParams.YscaleNo >= 3 ? this.inputParams.YscaleNo : 6,
};
this.color = 'black';
this.type = _params.type;
this.params = _params;

二：绘制坐标轴Y轴

const _height = this.params.height;
const _pad = this.params.padding;
const _arrow = _pad + ',' + (_pad - 5) + ' ' + (_pad - 6) + ',' + (_pad + 12) + ' ' + (_pad + 6) + ',' + (_pad + 12);
 this.AxisY = {
   x1: _pad,
   y1: _height - _pad,
   x2: _pad,
   y2: _pad,
   arrow: _arrow
};

三、绘制Y轴的刻度

const _height = this.params.height;
const _width = this.params.width;
// 显示label的边距
const _padding = this.params.padding;
const _Ydata = this.params.yAxis.data;
// 显示的刻度数
const _YscaleNo = this.params.YscaleNo;
const _dataMax = this.getMinAndMaxData(_Ydata).dataMax;
const _dataMin = this.getMinAndMaxData(_Ydata).dataMin;
let _YminValue;
let _YgapValue;
if (_dataMin < 0) {
   _YgapValue = Math.ceil((_dataMax - _dataMin) / (_YscaleNo) / 10) * 10;
   _YminValue = Math.floor(_dataMin / _YgapValue) * _YgapValue;
} else {
   _YgapValue = Math.ceil((_dataMax) / (_YscaleNo) / 10) * 10;
   _YminValue = 0;
}
// Y轴坐标点
const _y2 = this.AxisY.y2;
const _y1 = this.AxisY.y1;
const _x1 = this.AxisY.x1;
// Y轴刻度的间隙宽度
const _YgapWidth = (_y1 - _y2) / (this.params.YscaleNo);
this.valueToPxRatio = _YgapValue / _YgapWidth;
// 坐标轴（0,0）的Y轴坐标
const _Y0 = _y1 - Math.abs(_YminValue / this.valueToPxRatio);
this.Y0 = _Y0;
for (let i = 0; i < this.params.YscaleNo; i++) {
   const _obj: Scale = { x1: 0, x2: 0, y1: 0, y2: 0, label: '', value: 0 };
   _obj.x1 = _x1;
   _obj.y1 = _y1 - _YgapWidth * i;
   _obj.x2 = _x1 + _width - 2 * _padding;
   _obj.y2 = _y1 - _YgapWidth * i;
   _obj.label = _YminValue + _YgapValue * i;
   this.Yscale.push(_obj);
}

四、绘制X坐标轴

const _width = this.params.width;
// 显示label的边距
const _pad = this.params.padding;
const _x2 = _width - _pad;
const _y2 = this.Y0;
const _arrow = (_x2 + 5) + ',' + _y2 + ' ' + (_x2 - 10) + ',' + (_y2 - 6) + ' ' + (_x2 - 10) + ',' + (_y2 + 6);
this.AxisX = {
  x1: _pad,
  y1: _y2,
  x2: _x2,
  y2: _y2,
  arrow: _arrow
};

五、绘制X轴刻度

const _width = this.params.width;
const _Xdata = this.params.xAxis.data;
const _Ydata = this.params.yAxis.data;
const Y0 = this.Y0;
const _x1 = this.AxisX.x1;
const _x2 = this.AxisX.x2;
const XgapWidth = ((_x2 - _x1) / (this.params.xAxis.data.length + 1));
this.XgapWidth = XgapWidth;
for (let i = 0; i < _Xdata.length; i++) {
   const _obj: Scale = { x1: 0, x2: 0, y1: 0, y2: 0, value: 0, label: '' };
   _obj.y1 = Y0;
   _obj.y2 = Y0 + 5;
   _obj.label = _Xdata[i];
   _obj.value = _Ydata[i];
   _obj.x1 = _x1 + XgapWidth * (i + 1);
   _obj.x2 = _x1 + XgapWidth * (i + 1);
   this.Xscale.push(_obj);

六、绘制矩形

const _value = this.params.yAxis.data;
const _dataPadding = this.params.dataPadding;
const _XgapWidth = this.XgapWidth;
for (let i = 0; i < _value.length; i++) {
   const element = _value[i];
   const _obj: Chart = { x: 0, y: 0, w: 0, h: 0, value: 0 };
   _obj.w = _XgapWidth - 2 * _dataPadding;
   _obj.x = this.Xscale[i].x1 - _obj.w - _dataPadding;
   _obj.h = Math.abs(this.Xscale[i].value / this.valueToPxRatio);
   _obj.value = this.Xscale[i].value;
   if (this.Xscale[i].value >= 0) {
      _obj.y = this.Y0 - (this.Xscale[i].value) / this.valueToPxRatio;
   } else {
      _obj.y = this.Y0;
   }
      this.data.push(_obj);
   }
}

七、绘制折线

const _data = this.data;
let _str = '';
_data.forEach(ele => {
if (ele.value < 0) {
   ele.y = ele.y + ele.h;
}
   _str += (ele.x + ele.w / 2) + ',' + ele.y + ' ';
});
this.polyLinePoints = _str;

更多关于AngularJS相关内容感兴趣的读者可查看本站专题：《AngularJS指令操作技巧总结》、《AngularJS入门与进阶教程》及《AngularJS MVC架构总结》

希望本文所述对大家AngularJS程序设计有所帮助。