Definitions

Definitions are objects that a PDF can contain, for example, text, images, tables, columns, etc. All of these definitions extend from StyleDefinition, which is an abstract class that contains all the styles (alignment, color, bold, etc...) that a definition can apply. This class is not exported, it is internally used in the library.

IMPORTANT

Since definitions extend from StyleDefinition, all styles are available to those definitions, but some methods won't work with some of them, for example, you can not bold an image.

To use a definition you need to import it and then instantiate it. A definition can apply multiple styles by calling methods next to each other by chaining them and when you are done, use end property to return the resulting object (this result is the format pdfmake knows), the only exception is when using images, since loading an image is asynchronously, this needs to be treated differently, continue reading to learn about it.

Each definition has its own result type (interface) when calling end property, it returns an object which has its own type, for example, when using Txt definition class, it corresponds to IText, when using a Ol (ordered list), it corresponds to IOl and so on. This types (interfaces) show us the possible properties these objects can have, but some properties are optional.

KEPP IN MIND

Most classes are called as the original pdfmake library properties (columns, tables, etc..), but there are exceptions like text which is represented as Txt, it's the same with Image which is represented as Img. The reason is that there are existing native objects in the browser like Image and Text.

Here are some definition examples with their corresponding result type.

Using a single text:

import { Txt, IText } from 'pdfmake-wrapper';

const text: IText = new Txt('hi!').bold().end;

/**
 * text result:
 * { text: 'hi!', bold: true }
*/

// It's a must finish with end property to return the built object, otherwise, it'll return the Text Class

Using an ordered list:

import { Ol, IOl } from 'pdfmake-wrapper';

const ol: IOl = new Ol([
    'item 1',
    'item 2'
]).type('upper-roman').end;

/**
 * ol result:
 * {
 *      type: 'upper-roman',
 *      ol: [
 *          'item 1',
 *          'item 2'
 *      ]
 * }
*/

As we mentioned early, images are treated differently, instead of using end property when finishing to styled them, you need to call build() method, which will return a promise with the object result.

Calling then method.

import { Img, IImg } from 'pdfmake-wrapper';

new Img('http://domain.com/picture1.jpeg').build().then((result: IImg) => {
    /**
     * Result:
     * { image: 'data:image/png;base64, ...' }
    */
});

Using async/await:

import { Img, IImg } from 'pdfmake-wrapper';

const result: IImg = await new Img('http://domain.com/picture1.jpeg').build();
/**
 * Result:
 * { image: 'data:image/png;base64, ...' }
*/

You can take a look to the definition list in API References or some usage in Guides section.