---
title: "registerOnLayoutRectChanged"
description: "Registers a [callback] to be executed with the position of this modifier node relative to the
coordinate system of the root of the composition, as well as in screen coordinates and window
coordinates. This will be called after layout pass. This API allows for throttling and debouncing
parameters in order to moderate the frequency with which the callback gets invoked during high
rates of change (e.g. scrolling).

Specifying [throttleMillis] will prevent [callback] from being executed more than once over that
time period. Specifying [debounceMillis] will delay the execution of [callback] until that amount
of time has elapsed without a new position.

Specifying 0 for both [throttleMillis] and [debounceMillis] will result in the callback being
executed every time the position has changed. Specifying non-zero amounts for both will result in
both conditions being met."
type: "function"
---

<div class='type'>Function</div>


<a id='references'></a>
<div class='sourceset sourceset-common'>Common</div>


```kotlin
fun DelegatableNode.registerOnLayoutRectChanged(
    throttleMillis: Long,
    debounceMillis: Long,
    callback: (RelativeLayoutBounds) -> Unit,
): RegistrationHandle
```


Registers a `callback` to be executed with the position of this modifier node relative to the
coordinate system of the root of the composition, as well as in screen coordinates and window
coordinates. This will be called after layout pass. This API allows for throttling and debouncing
parameters in order to moderate the frequency with which the callback gets invoked during high
rates of change (e.g. scrolling).

Specifying `throttleMillis` will prevent `callback` from being executed more than once over that
time period. Specifying `debounceMillis` will delay the execution of `callback` until that amount
of time has elapsed without a new position.

Specifying 0 for both `throttleMillis` and `debounceMillis` will result in the callback being
executed every time the position has changed. Specifying non-zero amounts for both will result in
both conditions being met.

#### Parameters

| | |
| --- | --- |
| throttleMillis | The duration, in milliseconds, to prevent `callback` from being executed more than once over that time period. |
| debounceMillis | The duration, in milliseconds, to delay the execution of `callback` until that amount of time has elapsed without a new position. |
| callback | The callback to be executed. |


#### Returns

| | |
| --- | --- |
|  | an object which should be used to unregister/dispose this callback |