Awesome Charts in Angular 13 with ng2-charts

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  • Post last modified:February 3, 2023
  • Post category:angular / chart
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  • Reading time:6 mins read

Charts help us to visualize large amounts of data in an easy-to-understand and interactive way.  

In angular, we have various charting libraries to create charts. In the previous article, we have seen Data visualization with ECharts in angular using ngx-echarts.

Angular Charts Series Articles

In this article, we will develop awesome charts in angular 13 with ng2-charts.

We will see,

  • Introduction about the ng2-charts
  • Different ways to install ng2-charts in angular.
  • Create a bar chart
  • Create a line chart

Introduction

ng2-charts is an open-source chart library based on chart.js. 

Chart.js is a popular javascript charting library. ng2-charts is a wrapper around chart.js. It provides baseChart directive to render the chart.

ng2-charts has ~2K GitHub Stars and around 767k monthly downloads on npm.

angular ng2-charts github stars angular ng2-charts github forks angular ng2-charts licence angular ng2-charts NPM downloads

It supports the following chart types : 

  • Line Chart
  • Pie Chart 
  • Bar Chart
  • Doughnut Chart 
  • Radar Chart
  • Polar Area Chart 
  • Bubble Chart
  • Scatter Chart

Also provides many customization options like :

  • Responsiveness
  • Animation customization
  • Chart Title
  • Legends
  • Labels
  • Colors
  • Tooltip
  • Theming
  • Combine Charts
  • Options (as from chart.js documentation)

ng2-charts now also provides add and generate schematics for installation and generating above supported charts.

ng2-charts Installation

Create a new angular application using the following command
(Note: skip this step if you want to add ng2-charts in the existing angular application, At the time of writing this article I was using angular 13). 

ng new angular-ng2-charts-demo

We have two ways to install ng2-charts in angular application. 

  1. Using ng add schematic
  2. Manual installation

Installing ng2-charts using ng add schematic

This is an easy way to install ng2-charts in angular. Execute the following ng add schematic command

ng add ng2-charts

This command,

  • automatically installs the ng2-charts and chart.js libraries and
  • Imports and add NgChartsModule in app.module.ts to start using the library right away.

If you get the error : 

Cannot find module '@angular/cdk/schematics'

Install @angular/cdk with following command

npm install --save @angular/cdk

Manually install ng2-charts

  1. Install the ng2-charts and chart.js package using following commands

    npm install ng2-charts --save
    npm install chart.js --save

2. Import the NgChartsModule in your app main module.

So our final AppModule will look like:

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';

import { AppComponent } from './app.component';
import { NgChartsModule } from 'ng2-charts';

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule,
    NgChartsModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

Great, Installation steps are done. Now let’s see how to develop charts using ng2-charts. We will create a bar chart to show monthly sales data.

Create Bar chart using ng2-Charts

ng2-charts has one directive for all chart types: baseChart. We will use this directive on canvas to render the chart.

Let’s first prepare the chart data.

Prepare Chart Data

We will create chart data as below, for the demo I am using static data.

  salesData: ChartData<'bar'> = {
    labels: ['Jan', 'Feb', 'Mar', 'Apr', 'May'],
    datasets: [
      { label: 'Mobiles', data: [1000, 1200, 1050, 2000, 500] },
      { label: 'Laptop', data: [200, 100, 400, 50, 90] },
      { label: 'AC', data: [500, 400, 350, 450, 650] },
      { label: 'Headset', data: [1200, 1500, 1020, 1600, 900] },
    ],
  };

  • labels : It is the x axis labels. It’s necessary for charts: line, bar and radar. And just labels (on hover) for charts: polarArea, pie and doughnut. Label is either a single string, or it may be a string[] representing a multi-line label where each array element is on a new line.
  • datasets: datasets is an array of multiple series. each series represent different dataset. here label is shown as the legend and value will be mapped to the respecitve x-axis label.

Chart Options

We can customize charts using various chart options.

chartOptions: ChartOptions = {
    responsive: true,
    plugins: {
      title: {
        display: true,
        text: 'Monthly Sales Data',
      },
    },
  };

There are many other customization options available. Check out more options at Chart.JS Documentation.

Add chart canvas on template

Now to render chart on on-page, we have to add < canvas > on the template. We will use baseChart  as below.

Important input properties of baseChart directive :

  • type: indicates the type of charts, it can be: line, bar, radar, pie, polarArea, doughnut
  • data: indicates the chart data object.
  • options: indicates the chart options object

Other additional properties: 

  • labels: instead of specifying x-axis labels in  ChartData, you can create a separate string array and assign it as an input property.
  • datasets: instead of specifying datasets in ChartData, we can pass that separate array as an input property.
  • colors: data colors, will use default and|or random colors if not specified.

<canvas baseChart 
        [data]="salesData" 
        [type]="'bar'"
        [options]="chartOptions"
      >
      </canvas>

It will generate chart as below.

Angular ng2-charts Bar Chart
Angular ng2-charts - Bar Chart

Line Chart

Same as the bar chart we can generate the line chart.

To create a smooth curve line chart we will add one additional property tension: 0.5 in datasets.

  salesData: ChartData<'line'> = {
    labels: ['Jan', 'Feb', 'Mar', 'Apr', 'May'],
    datasets: [
      { label: 'Mobiles', data: [1000, 1200, 1050, 2000, 500], tension: 0.5 },
      { label: 'Laptop', data: [200, 100, 400, 50, 90], tension: 0.5 },
      { label: 'AC', data: [500, 400, 350, 450, 650], tension: 0.5 },
      { label: 'Headset', data: [1200, 1500, 1020, 1600, 900], tension: 0.5 },
    ],
  };
<canvas
   baseChart
   [data]="salesData"
   [type]="'line'"
   [options]="chartOptions"
>
</canvas>
Angular ng2-charts - Line Chart

Final Code

import { Component } from '@angular/core';
import { ChartData, ChartOptions } from 'chart.js';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss'],
})
export class AppComponent {
  salesData: ChartData<'line'> = {
    labels: ['Jan', 'Feb', 'Mar', 'Apr', 'May'],
    datasets: [
      { label: 'Mobiles', data: [1000, 1200, 1050, 2000, 500], tension: 0.5 },
      { label: 'Laptop', data: [200, 100, 400, 50, 90], tension: 0.5 },
      { label: 'AC', data: [500, 400, 350, 450, 650], tension: 0.5 },
      { label: 'Headset', data: [1200, 1500, 1020, 1600, 900], tension: 0.5 },
    ],
  };

  chartOptions: ChartOptions = {
    responsive: true,
    plugins: {
      title: {
        display: true,
        text: 'Monthly Sales Data',
      },
    },
  };
}

<nav class="navbar navbar-expand navbar-dark bg-dark px-2">
  <a class="navbar-brand" href="#">NG2-CHARTS DEMO</a>
</nav>

<div class="container">
  <div class="card mt-2">
    <div class="card-body">
      <h4 class="card-title">Bar Chart</h4>
      <canvas
        baseChart
        [data]="salesData"
        [type]="'bar'"
        [options]="chartOptions"
      >
      </canvas>
    </div>
  </div>
  <div class="card mt-2">
    <div class="card-body">
      <h4 class="card-title">Line Chart</h4>
      <canvas
        baseChart
        [data]="salesData"
        [type]="'line'"
        [options]="chartOptions"
      >
      </canvas>
    </div>
  </div>
</div>

Result

Angular ng2-charts Bar Chart

Git Repository

https://github.com/ngdevelop-tech/angular-ng2-charts-demo

Resources

Summary

In this article, We have developed charts in angular 13 with ng2-charts.

We have seen

  • Different ways to install ng2-charts in angular app
  • Developed the bar chart and line chart using ng2-charts

I hope you like this article, please provide your valuable feedback and suggestions in the below comment section🙂.

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