Book Image

Learn Chart.js

By : Helder da Rocha
Book Image

Learn Chart.js

By: Helder da Rocha

Overview of this book

Chart.js is a free, open-source data visualization library, maintained by an active community of developers in GitHub, where it rates as the second most popular data visualization library. If you want to quickly create responsive Web-based data visualizations for the Web, Chart.js is a great choice. This book guides the reader through dozens of practical examples, complete with code you can run and modify as you wish. It is a practical hands-on introduction to Chart.js. If you have basic knowledge of HTML, CSS and JavaScript you can learn to create beautiful interactive Web Canvas-based visualizations for your data using Chart.js. This book will help you set up Chart.js in a Web page and show how to create each one of the eight Chart.js chart types. You will also learn how to configure most properties that override Chart’s default styles and behaviors. Practical applications of Chart.js are exemplified using real data files obtained from public data portals. You will learn how to load, parse, filter and select the data you wish to display from those files. You will also learn how to create visualizations that reveal patterns in the data. This book is based on Chart.js version 2.7.3 and ES2015 JavaScript. By the end of the book, you will be able to create beautiful, efficient and interactive data visualizations for the Web using Chart.js.
Table of Contents (14 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
Index

Fonts


Chart.js uses Canvas to select and display local and installed fonts. The font configuration involves setting up to four font properties: family, size, style, and color. A fontFamily is a string containing a list of font-family names, a fontStyle contains a string with the name of a style supported by the corresponding font-family, a fontColor is any valid CSS-compatible color string, and the fontSize is a number that represents the size in pixels. You can configure font attributes in any object that includes text: titles, tick captions, legend labels, or tooltips, or you can set global defaults that will be inherited by text elements that don't explicitly set font attributes.

Selecting standard fonts

The basic font properties are named fontFamily, fontSize, fontStyle, and fontColor. Some objects have prefixed versions of these same properties. These objects are listed as follows:

Object containing text element

Description

Font properties

Chart.defaults.global

Global defaults

defaultFontFamily...