Angular 8 & ChartJs 在饼图中改变颜色

Question

我正在尝试更改默认的饼图颜色。但所有 3 个饼图弧都显示为红色。将 pieColor 数组中的第一种颜色应用于所有弧。我正在使用 chart.js 2.9.3、ng2-charts 2.3.0 和 angular 8。此外，我正在尝试不同的颜色格式，如十六进制代码或 RGB，但无法正常工作。

pie-chart.component.html

<div class="chart-wrapper">
    <canvas baseChart 
    [data]="doughnutChartData"
    [labels]="doughnutChartLabels"
    [colors]="pieColor
    [chartType]="doughnutChartType">
  </canvas>
</div>

pie-chart.component.ts

import { Component } from '@angular/core';
import { ChartType } from 'chart.js';
import { MultiDataSet, Label } from 'ng2-charts';

@Component({
  selector: 'app-doughnut-chart',
  templateUrl: './doughnut-chart.component.html',
  styleUrls: ['./doughnut-chart.component.css']
})

export class DoughnutChartComponent {

  doughnutChartLabels: Label[] = ['BMW', 'Ford', 'Tesla'];
  doughnutChartData: MultiDataSet = [
    [55, 25, 20]
  ];
  doughnutChartType: ChartType = 'doughnut';
  public pieColor: Color[] = [
     { backgroundColor: 'red' },
     { backgroundColor: 'green' },
     { backgroundColor: 'blue' }
  ]
}

输出

Answer 1

您的问题是颜色数组的形式。不要定义多个 backgroundColor 数组，每个数组都有一种颜色，而应该只定义一个数组，它有多种颜色。试试下面，它应该工作:

模板

<div class="chart-wrapper">
  <canvas baseChart [data]="doughnutChartData" [labels]="doughnutChartLabels" [colors]="colors"
    [chartType]=" doughnutChartType">
  </canvas>
</div>

Controller

export class AppComponent {
  doughnutChartLabels: Label[] = ['BMW', 'Ford', 'Tesla'];

  doughnutChartData: MultiDataSet = [
    [
      55,
      25,
      20
    ]
  ];

  doughnutChartType: ChartType = 'doughnut';

  colors: Color[] = [
    {
      backgroundColor: [
        'red',
        'green',
        'blue'
      ]
    }
  ];

}