The message states that the variable "Chart" has not been defined

I have been attempting to integrate ChartJS with Angular2, but I keep encountering an error message stating that 'Chart is not defined'. I made sure to install the ChartJS typings and referenced them accordingly. Additionally, I included the chartjs script in the index.html file. Can someone point out what might be causing this issue?

/// <reference path="../../website/typings/main/ambient/chart/index.d.ts" />
import {Directive, ElementRef, Renderer, Input} from 'angular2/core';

@Directive({
    selector: '[chart]'
})
export class ChartDirective {
    constructor(el: ElementRef, renderer: Renderer) {
        //el.nativeElement.style.backgroundColor = 'yellow';
        var data = {
            labels: ["January", "February", "March", "April", "May", "June", "July"],
            datasets: [
                {
                    label: "My First dataset",
                    fillColor: "rgba(220,220,220,0.2)",
                    strokeColor: "rgba(220,220,220,1)",
                    pointColor: "rgba(220,220,220,1)",
                    pointStrokeColor: "#fff",
                    pointHighlightFill: "#fff",
                    pointHighlightStroke: "rgba(220,220,220,1)",
                    data: [65, 59, 80, 81, 56, 55, 40]
                },
                {
                    label: "My Second dataset",
                    fillColor: "rgba(151,187,205,0.2)",
                    strokeColor: "rgba(151,187,205,1)",
                    pointColor: "rgba(151,187,205,1)",
                    pointStrokeColor: "#fff",
                    pointHighlightFill: "#fff",
                    pointHighlightStroke: "rgba(151,187,205,1)",
                    data: [28, 48, 40, 19, 86, 27, 90]
                }
            ]
        };
        var ctx: any = el.nativeElement.getContext("2d");
        var lineChart = new Chart(ctx);
        ////var lineChartOptions = areaChartOptions;
        ////lineChartOptions.datasetFill = false;
        lineChart.Line(data);
    }
}

UPDATE:

This is how my index.html file looks:

<html>
<head>
    <title>DBL Information Systems</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="styles.css">

    <!-- 1. Load libraries -->
    <!-- IE required polyfills, in this order -->
    <script src="node_modules/es6-shim/es6-shim.min.js"></script>
    <script src="node_modules/systemjs/dist/system-polyfills.js"></script>
    <script src="node_modules/angular2/es6/dev/src/testing/shims_for_IE.js"></script>

    <script src="node_modules/angular2/bundles/angular2-polyfills.js"></script>
    <script src="node_modules/systemjs/dist/system.src.js"></script>
    <script src="node_modules/rxjs/bundles/Rx.js"></script>
    <script src="node_modules/angular2/bundles/angular2.dev.js"></script>

    <script src="node_modules/chartjs/chart.js"></script>

    <!-- 2. Configure SystemJS -->
    <script>
        System.config({
            packages: {
                app: {
                    format: 'register',
                    defaultExtension: 'js'
                }
            }
        });
        System.import('app/main')
                .then(null, console.error.bind(console));
    </script>
</head>

<!-- 3. Display the application -->
<body>
<my-app>Loading...</my-app>
</body>
</html>

Here is an image of my typings folder structure for reference:

https://i.sstatic.net/7tNEA.png

Answer №1

To include the Chart class in your code, you must use an import statement like this:

import {Chart} from 'chartjs';

The specific configuration for SystemJS will impact how you import external dependencies.

Typings are primarily used for enhancing code completion and checking during development in your chosen IDE.

Modification

If you want to configure SystemJS for the 'chartjs' library, here is an example setup:

System.config({
  map: {
    chartjs: 'node_modules/chartjs/chart.js'
  },
  (...)
});

You can also explore this plunkr demo: https://plnkr.co/edit/IA2LojT2CXV9qcCDOdBl?p=preview.

Update

For adding typings, consider these steps:

  • Install the TypeScript type definitions for the library via npm

    npm install --save-dev retyped-chartjs-tsd-ambient
    
  • Use Typings to import the typings into your project

    typings install --save --ambient file:node_modules/retyped-chartjs-tsd-ambient/chart.d.ts
    
  • If there's an issue with module naming in the d.ts file, wrap it with a declare module clause to address it:

    declare module 'chartjs' {
      interface ChartDataSet {
        label: string;
      (...)
    }
    

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