Chart.js Doughnut plugin to allow for lines of text in the middle

Chart.js plugin module that allows to display multiple lines of text centered in the middle area of the doughnut charts. This plugin is forked from https://github.com/ciprianciurea/chartjs-plugin-doughnutlabel to provide support for Chart.js v3 as well as some other improvements and bug fixes. This is a BREAKING change meaning this plugin will NOT work with Chart.js v3.

Demo

Have a look at the Demo page.

Table of contents

- Installation
- Usage example
- Development
- License

Installation

Install through yarn:

``bash
yarn install chartjs-plugin-doughnutlabel-rebourne
`

Don't forget to install v3 of Chart.js:

`bash
yarn install chart.js@next
`

After that, you need to activate the plugin, either globally :

`js
Chart.plugins.register(DoughnutLabel);
`

or for each chart separately:

`js
new Chart(ctx, {
plugins: [DoughnutLabel],
});
`

Usage

Below is a table with available options:

| Option | Description | Label Scope | Plugin Scope | Global Scope |
| ------------------- | -------------------------------------------------------------------------------------------------------------------------------- | :---------: | :----------: | :----------: |
| paddingPercentage | add padding when scaling text larger than inner circle (defaults to 10) | | ✓ | ✓ |
| labels | array of labels (objects) | | ✓ | |
| color | css property | ✓ | ✓ | ✓ |
| font.family | css property | ✓ | ✓ | ✓ |
| font.lineHeight | css property | ✓ | ✓ | ✓ |
| font.size | css property | ✓ | ✓ | ✓ |
| font.style | css property | ✓ | ✓ | ✓ |
| font.weight | css property | ✓ | ✓ | ✓ |
| font.string | all previous font properties in one string separated by space | ✓ | ✓ | ✓ |
| text | value of label (can be string or function) | ✓ | | |
| display | show label or not | ✓ | ✓ | ✓ |
| api\* | plugin core api (defaults to beforeDatasetDraw) | | ✓ | ✓ |

\*Option api is a really-low level and intended for developers and those who are familar with internal workings of Chart.js (or have experience making plugins).

Note that more specific scope will override more global. For example, if you declare color in plugin scope and in label scope, value from label scope will win.

Options with global scope have a special meaning - they will always have a default value, i.e. if other scopes have no value, the final option will taken from Chart.defaults scope.

`js
Chart.defaults.plugins.doughnutlabel = {}; // global scope

options: {
plugins: {
doughnutlabel: { // plugin scope
paddingPercentage: 5,
labels: [
{ // label scope
text: 'Text' or functionName,
font: {
size: '24',
family: 'Arial, Helvetica, sans-serif',
style: 'italic',
weight: 'bold',
},
color: '#bc2c1a',
},
],
},
},
},
`

Usage without a module bundler

Using CDN is probably the best way - jsDelivr. Select the .min file with SRI parameters for extra safety. If you need to debug any issues, select the full version instead.

Alternatively, the plugin can be manually downloaded from the
Releases page on GitHub!

`html

`

or use the minified version

`html

`

Development

You first need to install node dependencies (requires Node.js):

`bash
yarn install
`

The following commands are available via package.json:

| Command | Purpose |
| :------------------- | :---------------------------------------------- |
| yarn lint | perform code linting |
| yarn build | build dist files |
| yarn build --watch | build and watch for changes (inc. browser-sync) |
| yarn package | create an archive with dist files and samples |

License

chartjs-plugin-doughnutlabel` is available under the MIT license.