window.IntersectionObserver
See: IntersectionObserver
Since: v8.1
IntersectionObserver(callback, [options])
Provides a mechanism to asynchronously observe changes in the intersection of a target element with an ancestor element or with a top-level document element.
Throws:
SyntaxErrorIf therootMarginorscrollMarginvalues are invalid.RangeErrorIf anythresholdvalues are outside the range of 0.0 to 1.0.
| Param | Type | Default | Description |
|---|---|---|---|
callback | function | The function called whenever an intersection event is triggered. | |
[options] | Object | {} | Options to configure the observation. |
[options.root] | Element | `` | The element that is used as the viewport for checking visibility of the target. If not specified, the document's viewport is used. |
[options.rootMargin] | string | "\"0px\"" | Margin around the root. Can have values similar to the CSS margin property. |
[options.scrollMargin] | string | "\"0px\"" | Margin applied to the scroll container during intersection calculation. |
[options.threshold] | number | Array<number> | 0 | A single number or an array of numbers indicating at what percentage of the target's visibility the observer's callback should be executed. |
root : Element
Gets the root element being used for intersection calculation.
See: IntersectionObserver - root
Since: v8.1
rootMargin : string
Gets the root margin applied to the intersection calculation.
See: IntersectionObserver - rootMargin
Since: v8.1
thresholds : Array<number>
Gets the list of thresholds used for triggering the observer's callback.
See: IntersectionObserver - threshold
Since: v8.1
scrollMargin : string
Gets the scroll margin applied to the scroll container during intersection calculation.
See: IntersectionObserver - scrollMargin
Since: v8.1
observe(target)
Starts observing the specified target element for intersection changes.
Throws:
TypeErrorIf the target is not an instance ofElement.
See: IntersectionObserver - observe
Since: v8.1
| Param | Type | Description |
|---|---|---|
target | Element | The element to be observed. |
unobserve(target)
Stops observing the specified target element.
Throws:
TypeErrorIf the target is not an instance ofElement.
See: IntersectionObserver - unobserve
Since: v8.1
| Param | Type | Description |
|---|---|---|
target | Element | The element to stop observing. |
disconnect()
Disconnects the IntersectionObserver instance from all observed target elements.
See: IntersectionObserver - disconnect
Since: v8.1
takeRecords()
Returns a list of IntersectionObserverEntry objects for all observed elements.
Returns: Array<IntersectionObserverEntry> - An array of IntersectionObserverEntry objects.
See: IntersectionObserver - takeRecords
Since: v8.1
