README.md

❧ react-typesetting ☙

React components for creating beautifully typeset designs.

Demo!

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⚠️ This project is highly experimental. Use at your own risk!

Table of Contents

• Components
  • TightenText
    • Props
  • PreventWidows
    • Props
  • Justify
    • Props
  • FontObserver
    • Props
  • FontObserver.Provider
    • Props
  • Typesetting.Provider
    • Props

Components

TightenText

import { TightenText } from 'react-typesetting';

Tightens word-spacing, letter-spacing, and font-size (in that order) by the minimum amount necessary to ensure a minimal number of wrapped lines and overflow.

The algorithm starts by setting the minimum of all values (defined by the minWordSpacing, minLetterSpacing, and minFontSize props) to determine whether adjusting these will result in fewer wrapped lines or less overflow. If so, then a binary search is performed (with at most maxIterations) to find the best fit.

By default, element resizes that may necessitate refitting the text are automatically detected. By specifying the reflowKey prop, you can instead take manual control by changing the prop whenever you’d like the component to update.

Note that unlike with typical justified text, the fit adjustments must apply to all lines of the text, not just the lines that need to be tightened, because there is no way to target individual wrapped lines. Thus, this component is best used sparingly for typographically important short runs of text, like titles or labels.

Props

Name	Type		Default	Description
className	String			The class to apply to the outer wrapper span created by this component.
style	Object			Extra style properties to add to the outer wrapper span created by this component.
children	Node			The content to render.
minWordSpacing	Number		-0.02	Minimum word spacing in ems. Set this to 0 if word spacing should not be adjusted.
minLetterSpacing	Number		-0.02	Minimum letter spacing in ems. Set this to 0 if word spacing should not be adjusted.
minFontSize	Number		0.97	Minimum font-size in ems. Set this to 1 if font size should not be adjusted.
maxIterations	Number		5	When performing a binary search to find the optimal value of each CSS property, this sets the maximum number of iterations to run before settling on a value.
reflowKey	One of…   Number   String			If specified, disables automatic reflow so that you can trigger it manually by changing this value. The prop itself does nothing, but changing it will cause React to update the component.
reflowTimeout	Number			Debounces reflows so they happen at most this often in milliseconds (at the end of the given duration). If not specified, reflow is computed every time the component is rendered.
disabled	Boolean			Whether to completely disable refitting the text. Any fit adjustments that have already been applied in a previous render will be preserved.
onReflow	Function			A function to call when layout has been recomputed and the text is done refitting.
preset	String			The name of a preset defined in an outer Typesetting.Provider component. If it exists, default values for all other props will come from the specified preset.

PreventWidows

import { PreventWidows } from 'react-typesetting';

Prevents widows by measuring the width of the last line of text rendered by the component’s children. Spaces will be converted to non-breaking spaces until the given minimum width or the maximum number of substitutions is reached.

By default, element resizes that may necessitate recomputing line widths are automatically detected. By specifying the reflowKey prop, you can instead take manual control by changing the prop whenever you’d like the component to update.

Props

Name	Type		Default	Description
className	String			The class to apply to the outer wrapper span created by this component.
style	Object			Extra style properties to add to the outer wrapper span created by this component.
children	Node			The content to render.
maxSubstitutions	Number		3	The maximum number of spaces to substitute.
minLineWidth	One of…   Number   String   Function		15%	The minimum width of the last line, below which non-breaking spaces will be inserted until the minimum is met. Numbers indicate an absolute pixel width. Strings indicate a CSS width value that will be computed by temporarily injecting an element into the container and determining its width. Functions will be called with relevant data to determine a dynamic number or string value to return. This can be used, for example, to have different rules at different breakpoints – like a media query.
nbspChar	One of…   String   React Element   Function		\u00A0	A character or element to use when substituting spaces. Defaults to a standard non-breaking space character, which you should almost certainly stick with unless you want to visualize where non-breaking spaces are being inserted for debugging purposes, or adjust their width. String values will be inserted directly into the existing Text node containing the space. React Element values will be rendered into an in-memory “incubator” node, then transplanted into the DOM, splitting up the Text node in which the space was found. Function values must produce a string, Text node, Element node, or React Element to insert.
reflowKey	One of…   Number   String			If specified, disables automatic reflow so that you can trigger it manually by changing this value. The prop itself does nothing, but changing it will cause React to update the component.
reflowTimeout	Number			Debounces reflows so they happen at most this often in milliseconds (at the end of the given duration). If not specified, reflow is computed every time the component is rendered.
disabled	Boolean			Whether to completely disable widow prevention.
onReflow	Function			A function to call when layout has been recomputed and space substitution is done.
preset	String			The name of a preset defined in an outer Typesetting.Provider component. If it exists, default values for all other props will come from the specified preset.

Justify

import { Justify } from 'react-typesetting';

While this may include more advanced justification features in the future, it is currently very simple: it conditionally applies text-align: justify to its container element (a <p> by default) depending on whether or not there is enough room to avoid large, unseemly word gaps. The minimum width is defined by minWidth and defaults to 16 ems.

You might also accomplish this with media queries, but this component can determine the exact width available to the container element instead of just the entire page.

Props

Name	Type		Default	Description
className	String			The class to apply to the outer wrapper element created by this component.
style	Object			Extra style properties to add to the outer wrapper element created by this component.
children	Node			The content to render.
as	One of…   String   Function   Object		p	The element type in which to render the supplied children. It must be a block level element, like p or div, since text-align has no effect on inline elements. It may also be a custom React component, as long as it uses forwardRef.
minWidth	One of…   Number   String		16em	The minimum width at which to allow justified text. Numbers indicate an absolute pixel width. Strings will be applied to an element's CSS in order to perform the width calculation.
initialJustify	Boolean		true	Whether or not to initially set text-align: justify before the available width has been determined.
reflowKey	One of…   Number   String			If specified, disables automatic reflow so that you can trigger it manually by changing this value. The prop itself does nothing, but changing it will cause React to update the component.
reflowTimeout	Number			Debounces reflows so they happen at most this often in milliseconds (at the end of the given duration). If not specified, reflow is computed every time the component is rendered.
disabled	Boolean			Whether to completely disable justification detection. The last alignment that was applied will be preserved.
onReflow	Function			A function to call when layout has been recomputed and justification has been applied or unapplied.
preset	String			The name of a preset defined in an outer Typesetting.Provider component. If it exists, default values for all other props will come from the specified preset.

FontObserver

import { FontObserver } from 'react-typesetting';

A component for observing the fonts specified in the FontObserver.Provider component.

Props

Name	Type		Default	Description
children	Function			A function that will receive the current status of the observed fonts. The argument will be an object with these properties: fonts: An array of the fonts passed to FontObserver.Provider, each with a loaded and error property. loaded: Whether all observed fonts are done loading. error: If any fonts failed to load, this will be populated with the first error.

FontObserver.Provider

import { FontObserver } from 'react-typesetting';

A context provider for specifying which fonts to observe.

Props

Name	Type		Default	Description
fonts	Array of…   One of…     String     Object 1			The fonts to load and observe. The font files themselves should already be specified somewhere (in CSS), this component simply uses FontFaceObserver to force them to load (if necessary) and observe when they are ready. Each item in the array specifies the font family, weight, style, and stretch, with only family being required. Additionally, each item can contain a custom testString and timeout for that font, if they should differ from the defaults. If only the family name is needed, the array item can just be a string.
	1 Object
	family	String
	weight	One of…   Number   String
	style	String
	stretch	String
	testString	String
	timeout	Number
testString	String			A custom test string to pass to the load method of FontFaceObserver, to be used for all fonts that do not specify their own testString.
timeout	Number			A custom timeout in milliseconds to pass to the load method of FontFaceObserver, to be used for all fonts that do not specify their own timeout.
children	Node			The content that will have access to font loading status via context.

Typesetting.Provider

import { Typesetting } from 'react-typesetting';

A context provider for defining presets for all other react-typesetting components to use.

Props

Name	Type		Default	Description
presets	Object		{}	An object mapping preset names to default props. For example, given the value: { myPreset: { minFontSize: 1, maxIterations: 3 } } …the TightenText component could use this preset by specifying the preset prop: <TightenText preset="myPreset" />
children	Node			The content that will have access to the defined presets via context.