typekit/webfontloader
Webfontloader
Webfontloader est une bibliothèque JavaScript et une API standardisée pour récupérer et gérer les polices web provenant de multiples fournisseurs externes et feuilles de style personnalisées. Elle fonctionne comme un gestionnaire d'état de chargement de polices qui coordonne la récupération des assets typographiques via une interface unifiée.
Le projet se concentre spécifiquement sur la prévention du flash de texte invisible en gérant les états de chargement et les timeouts. Il se distingue en fournissant un mécanisme pour synchroniser la typographie à travers différents contextes de navigation, incluant la capacité d'injecter une logique de chargement de police dans les fenêtres enfants et les iframes.
La bibliothèque suit le cycle de vie du chargement des polices pour déclencher des callbacks JavaScript et appliquer des classes CSS à la racine du document. Ces capacités permettent un contrôle précis sur les transitions visuelles, incluant l'utilisation de styles de secours lorsque le rendu de la police dépasse une durée définie.
Features
- Font Loading Libraries - Provides a comprehensive JavaScript interface for orchestrating web font loading with standardized event tracking and state management.
- Web Font Loaders - Provides a unified library for fetching and integrating web fonts from multiple external providers.
- Loading Timeouts - Implements configurable durations for font requests to trigger fallback styles if rendering is delayed.
- FOIT Prevention - Provides a specialized system to prevent the flash of invisible text using loading states and timeouts.
- Font Loading Transitions - Manages loading states and timeouts to eliminate the flash of invisible text before fonts render.
- Lifecycle Event Hooks - Triggers asynchronous callbacks at specific stages of the font loading process to respond to state changes.
- Loading Timeout Controllers - Implements programmatic timers to define maximum wait times for font rendering before switching to fallback styles.
- Cross-Provider Font Loaders - Unifies the fetching of fonts from multiple distinct providers into a single standardized API.
- Loading State Tracking - Monitors the progress of font loading to trigger UI changes or callbacks when fonts are requested, rendered, or fail.
- Loading Event Coordination - Triggers JavaScript callbacks and document style updates during the loading lifecycle to manage visual transitions.
- Loading State Managers - Orchestrates UI updates and CSS class application based on the current loading status of fonts.
- Provider Abstractions - Provides a unified interface to normalize font requests across various third-party typography providers.
- Font Glyph Validation - Verifies the correct rendering of specific font subsets and private glyphs using character strings.
- Font Glyph Verification - Verifies the presence of required glyphs in custom font sources using configurable test strings.
- Cross-Context Font Loading - Directs font loading requests from a parent window into same-origin iframe child contexts.
- Font Loading Behavior Controls - Allows modification of loading parameters and target windows to optimize typography rendering.
- Font Renderers - Tracks when fonts are requested or rendered to provide precise control over the visual presentation.
- Render Detection - Measures character dimensions to verify that a font has successfully rendered in the browser viewport.
- Font Synchronizers - Provides mechanisms to propagate font loading states and styles from a parent window into embedded iframe contexts.
- DOM-Driven State Management - Applies CSS classes to the document root to manage state and visual transitions during font retrieval.
- Asset Loading Injection - Injects font loading logic into child window frames to ensure typography consistency across embedded documents.
- Font Management - Control font loading behavior and events.
- Typography Libraries - Library for controlling web font loading.
- Web Typography Utilities - Control over font loading via @font-face.
