This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The IntersectionObserverEntry interface's read-only isIntersecting property is a Boolean value which is true if the target element intersects with the intersection observer's root. If this is true, then, the IntersectionObserverEntry describes a transition into a state of intersection; if it's false, then you know the transition is from intersecting to not-intersecting.
var isIntersecting = IntersectionObserverEntry.isIntersecting;
A Boolean value which indicates whether the target element has transitioned into a state of intersection (true) or out of a state of intersection (false).
In this simple example, an intersection callback is used to update a counter of how many targeted elements are currently intersecting with the intersection root.
function intersectionCallback(entries) {
entries.forEach(function(entry) {
if (entry.isIntersecting) {
intersectingCount += 1;
} else {
intersectingCount -= 1;
}
});
} To see a more concrete example, take a look at Handling intersection changes in Timing element visibility with the Intersection Observer API.
| Specification | Status | Comment |
|---|---|---|
| Intersection Observer The definition of 'IntersectionObserverEntry.isIntersecting' in that specification. | Working Draft | Initial definition |
| Feature | Chrome | Edge | Firefox | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|---|
| Basic support | 51 | No |
53 — 551 55 |
No | ? | ? |
| Feature | Android webview | Chrome for Android | Edge mobile | Firefox for Android | IE mobile | Opera Android | iOS Safari |
|---|---|---|---|---|---|---|---|
| Basic support | 51 | 51 | No | ? | No | ? | ? |
1. From version 53 until version 55 (exclusive): this feature is behind the dom.IntersectionObserver.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.
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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/IntersectionObserverEntry/isIntersecting