IntersectionObserver extension type

The IntersectionObserver interface of the Intersection Observer API provides a way to asynchronously observe changes in the intersection of a target element with an ancestor element or with a top-level document's . The ancestor element or viewport is referred to as the root.

When an IntersectionObserver is created, it's configured to watch for given ratios of visibility within the root. The configuration cannot be changed once the IntersectionObserver is created, so a given observer object is only useful for watching for specific changes in degree of visibility; however, you can watch multiple target elements with the same observer.

API documentation sourced from MDN Web Docs.

on
Implemented types
Available extensions

Properties

asString → String

Available on JSAny, provided by the JSAnyExtension extension

no setter
asString → String?

Available on JSAny?, provided by the JSAnyNullableExtension extension

no setter
entries → Iterable<MapEntry<String, dynamic>>

Available on JSObject, provided by the JSObjectExtension extension

no setter
hashCode → int
The hash code for this object.
no setterinherited
isDefinedAndNotNull → bool

Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension

no setter
isElement → bool

Available on JSObject?, provided by the JSObjectWebExtension extension

no setter
isHTMLElement → bool

Available on JSObject?, provided by the JSObjectWebExtension extension

no setter
isNode → bool

Available on JSObject?, provided by the JSObjectWebExtension extension

no setter
isNull → bool

Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension

Whether this value corresponds to JavaScript null.
no setter
isTruthy → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of !!this in JavaScript.
no setter
isUndefined → bool

Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension

Whether this value corresponds to JavaScript undefined.
no setter
isUndefinedOrNull → bool

Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension

no setter
keys → Iterable<String>

Available on JSObject, provided by the JSObjectExtension extension

no setter
not → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of !this in JavaScript.
no setter
root → JSObject?
The IntersectionObserver interface's read-only root property identifies the Element or Document whose bounds are treated as the of the for the element which is the observer's target.
no setter
rootMargin → String
The IntersectionObserver interface's read-only rootMargin property is a string with syntax similar to that of the CSS margin property. Each side of the rectangle represented by rootMargin is added to the corresponding side in the IntersectionObserver.root element's before the intersection test is performed. This lets you, for example, adjust the bounds outward so that the target element is considered 100% visible even if a certain number of pixels worth of width or height is clipped away, or treat the target as partially hidden if an edge is too close to the edge of the root's bounding box.
no setter
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
thresholds → JSArray<JSNumber>
The IntersectionObserver interface's read-only thresholds property returns the list of intersection thresholds that was specified when the observer was instantiated with IntersectionObserver.IntersectionObserver. If only one threshold ratio was provided when instantiating the object, this will be an array containing that single value.
no setter

Methods

add(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this + any in JavaScript.
and(JSAny? any) → JSAny?

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this && any in JavaScript.
as<T extends JSObject>() → T?

Available on JSObject, provided by the JSObjectExtension extension

callMethod<R extends JSAny?>(JSAny method, [JSAny? arg1, JSAny? arg2, JSAny? arg3, JSAny? arg4]) → R

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Calls method on this JSObject with up to four arguments.
callMethodVarArgs<R extends JSAny?>(JSAny method, [List<JSAny?>? arguments]) → R

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Calls method on this JSObject with a variable number of arguments.
dartify() → Object?

Available on JSAny?, provided by the JSAnyUtilityExtension extension

Converts a JavaScript JSON-like value to the Dart equivalent if possible.
delete(JSAny property) → JSBoolean

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Deletes the property with key property from this JSObject.
disconnect() → void
The IntersectionObserver method disconnect() stops watching all of its target elements for visibility changes.
divide(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this / any in JavaScript.
equals(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this == any in JavaScript.
exponentiate(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this ** any in JavaScript.
get(String key) → Object?

Available on JSObject, provided by the JSObjectExtension extension

getProperty<R extends JSAny?>(JSAny property) → R

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

The value of the property key property of this JSObject.
greaterThan(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this > any in JavaScript.
greaterThanOrEqualTo(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this >= any in JavaScript.
has(String property) → bool

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Shorthand helper for hasProperty to check whether this JSObject contains the property key property, but takes and returns a Dart value.
hasProperty(JSAny property) → JSBoolean

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Whether or not this JSObject contains the property key property.
instanceof(JSFunction constructor) → bool

Available on JSAny?, provided by the JSAnyUtilityExtension extension

Whether this JSAny? is an instanceof constructor.
instanceOfString(String constructorName) → bool

Available on JSAny?, provided by the JSAnyUtilityExtension extension

Whether this JSAny? is an instanceof the constructor that is defined by constructorName, which is looked up in the globalContext.
isA<T extends JSAny?>() → bool

Available on JSAny?, provided by the JSAnyUtilityExtension extension

Whether this JSAny? is an instance of the JavaScript type that is declared by T.
lessThan(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this < any in JavaScript.
lessThanOrEqualTo(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this <= any in JavaScript.
modulo(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this % any in JavaScript.
multiply(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this * any in JavaScript.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
notEquals(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this != any in JavaScript.
observe(Element target) → void
The IntersectionObserver method observe() adds an element to the set of target elements being watched by the IntersectionObserver. One observer has one set of thresholds and one root, but can watch multiple target elements for visibility changes in keeping with those.
or(JSAny? any) → JSAny?

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this || any in JavaScript.
put(Object key, Object? value) → void

Available on JSObject, provided by the JSObjectExtension extension

setProperty(JSAny property, JSAny? value) → void

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Write the value of property key property of this JSObject.
strictEquals(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this === any in JavaScript.
strictNotEquals(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this !== any in JavaScript.
subtract(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this - any in JavaScript.
takeRecords() → JSArray<IntersectionObserverEntry>
The IntersectionObserver method takeRecords() returns an array of IntersectionObserverEntry objects, one for each targeted element which has experienced an intersection change since the last time the intersections were checked, either explicitly through a call to this method or implicitly by an automatic call to the observer's callback.
toMap() → Map<String, dynamic>

Available on JSObject, provided by the JSObjectExtension extension

toString() → String
A string representation of this object.
inherited
typeofEquals(String typeString) → bool

Available on JSAny?, provided by the JSAnyUtilityExtension extension

Whether the result of typeof on this JSAny? is typeString.
unobserve(Element target) → void
The IntersectionObserver method unobserve() instructs the IntersectionObserver to stop observing the specified target element.
unsignedRightShift(JSAny? any) → JSNumber

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this >>> any in JavaScript.

Operators

operator ==(Object other) → bool
The equality operator.
inherited
operator [](String property) → JSAny?

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Shorthand helper for getProperty to get the value of the property key property of this JSObject, but takes a Dart value.
operator []=(String property, JSAny? value) → void

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Shorthand helper for setProperty to write the value of the property key property of this JSObject, but takes a Dart value.