blink::EventHandler (Blink core input handling)
Blink28623 Syys 2025

blink::EventHandler (Blink core input handling)

Scroll chain builder and overscroll chaining logic. Blink’s EventHandler is responsible for building the scroll chain (the sequence of nested scrollable ancestors) when the user scrolls an element . It determines how scroll events propagate up through parent containers and when to terminate the chain. Crucially, it respects the CSS overscroll-behavior of each element to decide if overscroll should propagate or stop at that element. For example, if an inner element is scrolled to its boundary, by default the scroll chains to its parent – but if that element’s style has overscroll-behavior: contain or none, the chain is broken and the overscroll is handled locally . To implement non-root elastic overscroll, one must modify how EventHandler (and associated scroll logic) interprets these style flags and sends overscroll events: instead of always bubbling to the root, it should allow an overscroll at the element itself when appropriate. In short, EventHandler is where the blink style system meets input: it ensures the scroll chain and overscroll-behavior rules are applied, so the developer must understand it to route overscroll to non-root scrollers.

Jaksot(394)

[General] Inside Blink: The Paint Property Tree Builder Pipeline

[General] Inside Blink: The Paint Property Tree Builder Pipeline

The PaintPropertyTreeBuilder is a critical component within Google Chrome’s Blink engine that converts layout data into structural property trees used for rendering. Operating during the PrePaint phas...

24 Joulu 202550min

Inside Blink: The Paint Property Tree Builder Pipeline

Inside Blink: The Paint Property Tree Builder Pipeline

The PaintPropertyTreeBuilder is a critical component within Google Chrome’s Blink engine that converts layout data into structural property trees used for rendering. Operating during the PrePaint phas...

24 Joulu 20251h 4min

Promisify Scroll: Promise-Based Web Scrolling API

Promisify Scroll: Promise-Based Web Scrolling API

The provided text describes a web platform initiative to modernize how browsers handle scrolling by having programmatic scroll methods return JavaScript Promises. Currently, functions like scrollTo() ...

24 Joulu 202528min

CSS Containing Blocks and Blink Engine Implementation

CSS Containing Blocks and Blink Engine Implementation

This text examines how CSS containing blocks function and how the Blink rendering engine implements these rules within Chromium. It explains that a containing block is the essential rectangular refere...

23 Joulu 202526min

Axis-Split Sticky Constraints in Chromium Layout and Compositing

Axis-Split Sticky Constraints in Chromium Layout and Compositing

Chromium is refining its rendering engine to support axis-split sticky constraints, allowing elements to stick to different scroll containers for horizontal and vertical movements. Previously, a singl...

23 Joulu 202533min

Mastering CSS Sticky Positioning and Scroll Containers

Mastering CSS Sticky Positioning and Scroll Containers

This documentation provides a comprehensive analysis of CSS sticky positioning, a hybrid layout scheme that anchors elements within their nearest scroll container while maintaining their space in the ...

20 Joulu 202534min

Blink Paint Property Trees: Construction and Lifecycle Phases

Blink Paint Property Trees: Construction and Lifecycle Phases

The provided text explains the construction and lifecycle of paint property trees within the Blink rendering engine. These structures, which include Transform, Clip, Effect, and Scroll trees, replace ...

20 Joulu 20251h 1min

Chromium's LayerTreeHostClient: The Compositing Bridge

Chromium's LayerTreeHostClient: The Compositing Bridge

The source provides an extensive overview of the LayerTreeHostClient interface, a crucial component in Chromium's rendering architecture that acts as the bridge between the content engine (like Blink ...

18 Joulu 202536min