AppLifecycleObserverService

Demonstrates detecting changes to an instance's ancestry by connecting to the `Class.Instance.AncestryChanged` event.

The ChangingPart's Parent is set to different values overtime. The parent of the part is the part's ancestor, so the `Class.Instance.AncestryChanged` event will fire whenever it changes.


Instance.AncestryChanged

child

parent

Instance.AttributeChanged

attribute

This sample demonstrates the subtleties of the Changed event on normal objects
and "-Value" objects.


This code sample demonstrates the Changed event firing within a parent object.


Instance.Changed

property

This snippet prints the names of objects as they are added to the Workspace:


Instance.ChildAdded

This snippet prints the names of objects as they are removed from the
Workspace:


Instance.ChildRemoved

This following example will print the name of any object that is added to the
Workspace:


Instance.DescendantAdded

descendant

The following example prints the name of any descendant as it is being removed
from the Workspace:


Instance.DescendantRemoving

This sample demonstrates how an Instance being destroyed remains in place
until the connected function yields.


Instance.Destroying

Instance.childAdded

Instance:AddTag

This example creates a Part and adds a few sparkle objects to the part. Then
it calls Part:ClearAllChildren() to remove all of the children.


Instance:ClearAllChildren

Demonstrates cloning a model using `Class.Instance:Clone()`.

Instance:Clone

Demonstrates destroying a Part using the `Class.Instance:Destroy()` function.

This function is the correct way to dispose of objects that are no longer required.


Instance:Destroy

Instance:FindFirstAncestor

name

Instance:FindFirstAncestorOfClass

className

Instance:FindFirstAncestorWhichIsA

The below would look in Workspace for an object name "Brick". If found, it
will change the name of the object to "Foo".


Instance:FindFirstChild

recursive

Instance:FindFirstChildOfClass

Instance:FindFirstChildWhichIsA

Instance:FindFirstDescendant

Instance:GetActor

Instance:GetAttribute

Instance:GetAttributeChangedSignal

Instance:GetAttributes

The below would print the name of all objects currently in Workspace when ran.


Instance:GetChildren

Instance:GetDebugId

scopeLength

GetDescendants is often used to do something to all the descendants that are a
particular type of object. The code in this example uses GetDescendants and
`Class.Instance:IsA()` to find all of the parts in the workspace and turns
them green.


Instance:GetDescendants

This code sample demonstrates the behavior of `Class.Instance:GetFullName()`.
It shows how the function behaves when called on an object not in the
`DataModel` hierarchy, and it also shows how the return value does not escape
special characters.


This code sample re-implements the `Class.Instance:GetFullName()` function in
Lua.


Instance:GetFullName

This code sample demonstrates how to save a value before a changed event fires
on it in order to get more information about a change.


This code sample demonstrates the equivalence of the `Changed` event and event
returned by `GetPropertyChangedSignal`.


Instance:GetPropertyChangedSignal

Instance:GetTags

Instance:HasTag

Demonstrates determining the class of Workspace using `Class.Instance:IsA()`

Workspace is of class 'Workspace', so the first statement is true.
Workspace is not of class 'BasePart', so the second statement is false.
Workspace inherits from Instance and therefore is of class 'Instance', so the third statement is true.


Instance:IsA

Demonstrates determining if one instance is the ancestor of another using `Class.Instance:IsAncestorOf()`

Workspace and SpawnLocation are ancestors of the SpawnLocation's decal.
Workspace is an ancestor of SpawnLocation.

SpawnLocation and its decal are descendants of Workspace, not ancenstors.
Decal is a descendant to SpawnLocation, not an ancestor.


Instance:IsAncestorOf

Instance:IsDescendantOf

ancestor

The following code demonstrates how a part can be re-added to the DataModel
after being removed:


Instance:Remove

Instance:RemoveTag

Instance:SetAttribute

value

The following code waits for an instance named "Part" to be added to
Workspace.


Instance:WaitForChild

childName

timeOut

Instance:children

Instance:clone

Instance:destroy

Instance:findFirstChild

Instance:getChildren

Instance:isA

Instance:isDescendantOf

Instance:remove

Instance

Instance.Archivable

Instance.Capabilities

Instance.ClassName

Instance.Name

Instance.Parent

Instance.RobloxLocked

Instance.Sandboxed

Instance.UniqueId

Instance.archivable

Instance.className

/reference/engine/classes/AppLifecycleObserverService.yaml

An `Class.Actor` is a container for code that can be safely split into its own thread.

Class

Actor

Luau

Array

Dictionary

Data Type

Objects

An object that runs connected functions upon a specific occurrence.

RBXScriptSignal

Variant

Data type having a value of either true or false.

bool

A double-precision floating-point number.

number

A sequence of characters, such as letters, numbers, and symbols.

string

void

Overview

Guides

Tutorials

Reference

Resources

Design

Engine

Avatar

Cloud

This field may be set when creating a resource, but may not be modified by subsequent requests.

This field may be provided in requests, but will never be included in responses.

Per API Key: {maxInPeriod} requests every {periodInSeconds} seconds per IP Address

This field may be set on responses, but will be ignored in requests.

The following API key permissions are required to call this endpoint. For more
information on generating proper keys, see [Managing API Keys]({apiKeyReferenceDocLink}).

The following endpoints are available at paths relative to the base URL.

This string is formatted as a [FieldMask](/cloud/reference/types#fieldmask).

A JSON value can be `null`, `boolean`, `string`, `number`, `array`, or `object`.

The following scopes are required for your OAuth 2.0 application to use this endpoint. For more information on how to register an OAuth 2.0 application, see [App Registration and Review]({oauth2ReferenceDocLink}).

The following objects describe payloads that are accepted or returned. See each individual endpoint for more information on when these objects are used.

This string is formatted as a [Timestamp](/cloud/reference/types#timestamp).

This allows viewing information about your assets.

This allows uploading and updating assets to Roblox.

Grants the ability to update badges owned by the user.

This allows you to view information about your Creator Store products.

This allows you to modify information about your Creator Store products.

This allows viewing information about your groups.

This allows you to manage group join requests for your account.

This allows viewing information about your inventory.

Grants access to read information about the experiences you follow.

Grants access to follow and unfollow experiences on your behalf.

Grants permission to read group information.

Grants access to read your localization tables.

Grants access to modify your localization tables.

Grants access to read your experiences' localization information.

Grants access to modify your experiences' localization preferences.

Grants access to modify user localization preferences.

This grants the ability to publish messages on behalf of users.

This allows sending notifications from your experience to users.

This allows listing secrets associated with your experience.

This allows creating and updating secrets associated with your experience.

Grants the ability to read place information.

Grants the ability to edit place information.

This operation grants access to publish new versions of experiences to Roblox.

Grants the ability to read experience information.

Grants the ability to edit experience information.

Allows you to view user restrictions in the experience.

Allows you to edit user restrictions in the experience.

Grants the ability to read user's premium and verified status.

This allows you to view a user's social accounts.

This enables Single Sign-On functionality.

This grants access to read your profile information.

Default Value: {defaultValueStart}{defaultValueEnd}

An array is an ordered list of values. Arrays are useful for storing collections of data.

A set of key-value pairs, where the keys can be any number, string, or object.

This function returns immediately if possible, but can yield the thread that called it until it can return a value.

{nameStart}name{nameEnd} is no longer supported or maintained by Roblox.

This math operation is no longer supported or maintained by Roblox.

This member doesn’t appear in the object browser and is not intended for widespread use.

This member is only accessible only through the command bar. Attempting to access this member from scripts causes an error.

This function can’t pause the Lua thread that called it.

Attempting to access this member in scripts causes an error. You might be able to access this member from Roblox Studio's property window.

This member doesn’t appear in Roblox Studio’s Object Browser.

You can’t create an instance of this class with the Instance.new constructor.

Roblox does not replicate this member across its server-client boundary.

Lua code can’t access this member. You might be able to change its value from the property window in Roblox Studio.

This object’s replication behavior is dependent on the player who owns it.

This member is accessible only through the command bar and plugins only. Attempting to access this member from scripts causes an error.

This member is read only. Attempting to write to this member causes an error.

This property is read-only and is safe to read in unsynchronized threads. Attempting to write to it causes an error.

This member is accessible only in CoreScripts.

Only Roblox CoreScripts can access this member, and it isn’t usable by Players.

You can read and write to this property safely from multiple threads.

This class is a top-level singleton. Retrieve an instance of this class with the GetService function.

Multiple threads can potentially write to this property, so it’s unsafe to read from unsynchronized threads.

This function pauses the Lua thread that called it until it returns a result. This doesn’t interrupt other scripts.

Learn how to create successful content on Roblox with comprehensive guides, code samples, reference, and tutorials.


{pageTitle} | {SiteName}

2D Paths

3D Art Overview

3D Importer

3D Workspace

9-Slice

AI Data Sharing

API Keys

About GDPR and CCPA

Accessibility Guidelines

Accessing Localization Settings

Accessory Fitting Tool

Account Verification

Acquisition

Activity Lessons

Adaptive Timestepping

Add New Models

Adding Animations

Adding Scripts

Adding Wings

Adding the Second Pose

Add to the Garage

Ads Manager

Advanced

Adventure Game Project

Adventure Game Pt. 1

Adventure Game Pt. 2

Adventure Game Pt. 3

Advertising

Advertising on Roblox

AlignOrientation

AlignPosition

Align Tool

All Cloud API

Analytics

Analytics Dashboard

Analytics Essentials

AngularVelocity

Animate in Roblox

Animating Characters

Animating Heads

Animating Parts

Animation

Animation Capture

Animation Editor

Animation Events

Animations and Feedback

Appearance

Apply Polished Assets

Applying Surface Images

Architecture

Armature Setup

Assemble an Asset Library

Assemblies

Assembling Modular Environments

Asset Manager

Asset Privacy

Assets

Assistant

Assistant for Documentation

Atmosphere

Audience

Audience Engagement

Audio Assets

Automatic Sizing

Automatic Skinning

Automatic Translations

Avatar Context Menu

Avatar Creation

Avatar Editor

Avatar Inspect Menu

Avatar Items

Avatar Preview

Avatar Setup

Avatar Tab

Avatar Tutorials

Back to Avatar Tutorials

Back to Guides

Back to Tutorials

Badges

Balancing Virtual Economies

BallSocket

Basic Gameplay

Basic Particle Effects

Battle Royale

Battle Royale Project

Beams

Become an Artist

Beginner Content

Being a Digital Citizen

Best Practices

Beta Features

Beta Testing Experiences

Beyond The Dark

Bindable

Blender Configurations

Blender Setup

Blender and Maya Export Settings

Bodies

Bodies - From Templates

Body Scale

Booleans

Bubble Chat

Build It, Play It Series

Build One Half

Building Studio Widgets

Building System

Building Unique 3D Objects

Building Your Business

Building a Ferris Wheel

Building a Hinged Door

Buildings and Props

Build the Roads

Built-In

Buttons

Buying Upgrades

CFrames

Caging

Caging Character Head

Caging Setup

Calisthenics Tool

Camera

Challenge Checkpoint 1

Challenge Checkpoint 2

Challenge Checkpoint 3

Change the Animation

Change the Script

Character Controllers

Characters

Chat

Chat with Voice

Classes

Classic Clothing

Classroom Best Practices

Classroom Facilitation

Cleanup

Cleanup and Reset

Client-Server Runtime

Clothing

Cloud Services

Clouds

Coding Abstraction

Coding Algorithms

Coding Fundamentals

Coding a Function

Coding a Question

Coding the Game Loop

Coding the Leaderboard

Coding the Story

Collaboration

Collaboration Best Practices

Collecting Items

Collisions

Colors and Textures

Combining Head Geometry

Comments

Community

Complete the City

Completing the Challenge

Complying with Advertising Standards

Conditionals

Connect the Beam

Console Guidelines

Construct Your World

Constructing the House

Containers

Content Updates

Contextual Purchases

Control Structures

Controlling the User's Camera

Core

Core Curriculum

Core Loops

Core Scripts

Create Basic Visual Effects

Create Player Hazards

Create Your First Experience

Create a Coin Collection Mechanic

Create a Project

Create an Environment with Terrain

Create and Destroy

Create the First Pose

Creating Animations

Creating Basic Heads

Creating Bundled Installers

Creating Elevators

Creating Engaging Experiences

Creating Face Accessories

Creating Flickering Lights

Creating Laser Beams

Creating Moving Objects

Creating Neon Signs

Creating Player Tools

Creating Private Servers

Creating Score Bars

Creating Seams and Unwrapping

Creating Spinning Objects

Creating Volcanoes

Creating Waterfalls

Creating a GUI

Creating a Health Pickup

Creating a Score Bar

Creating a Script

Creating a Sparkler

Creating a Texture Map

Creating an Animation

Creating and Publishing

Creating the Map

Creating with Module Scripts

Creation Overview

Creator Fund

Creator Store

Cross-Platform Design

Cross-Server Messaging

Current Release

Curve Editor

Custom

Custom Fields

Custom Particle Effects

Custom Thumbnails

Custom Translations

Customization

Customize Global Lighting

Customize and Share

Customizing In-Experience Text Chat

Cylindrical

DMCA Guidelines

Data Model

Data Stores

Data Structures

Data Types

Deadly Lava

Debugging

Designing Dark Soundscapes

Designing Educational Experiences

Designing For Roblox

Designing Poses

Designing Your Speeder

Designing a Map

Designing for Performance

Design the World

Detecting Hits

Detecting User Input

Develop Polished Assets

Developer Console

Developer Products

Developing a Moving World

Dictionaries and Arrays

Digital Citizenship

Disabling Default UI Elements

Discovery

Drag Detectors

Duplicate and Design

Dynamic Effects

Earning on Roblox

Economy Events

Educator Onboarding

Effects

Else/If Practice - Giving Points

Embedding and Exporting Textures

Emote Bar

Emotes

Ending Matches

Engagement

Engagement-Based Payouts

Enhancing Indoor Environments

Enhancing Outdoor Environments

Enhancing Outdoor Environments with Future Lighting

Enums

Environment

Environmental Art

Environments

Error Report

Errors

Event Organizers

Event Sequencer

Event Types

Events

Events Platform

Experience Guidelines

Experience Icons

Experience Notifications

Experience Thumbnails

Experienced Content

Experiences

Explorer Window

Export Settings

Exporting

Exporting Animations

Exporting Animations from Maya

Exporting Character Model

Exporting FBX

Exporting FBX from Blender

External Catalog Queries

External Tools

Extra Head Objects

FACS Poses Reference

Fading Trap

Featured Content

Features

Final Checks

Finishing Projects

Finishing and Add More

Finishing the Project

Finish the Blast

Finish the Challenge

Fitting and Conversion

Foundational Gameplay Systems

Frames

Frequently Asked Questions

Friends Locator

Functions

Functions and Events

Funnel Events

Galactic Speedway

Game Fund

Game Settings

Gamepad

Gameplay Scripting

Get Off the Ground

Get Started

Getting Featured on Roblox Owned Channels

Getting Started

Getting Started for Developers

Global Lighting

Global Wind

Globals

Glowing Lights with For Loops

Go Beyond the Challenge

Going for a Race

Go to Educator Onboarding

Greybox Your Environment

Greybox a Playable Area

Grouping the Parts

Groups

Growing Your Audience

Guidelines

Handling Requests

Hash Map

Heads

Highlighting

Hinge

Hit Detection with Lasers

Home Tab

Icons and Thumbnails

Identifying Issues

If/then Practice - Power ups

If/then Practice - Traps

Immersive Ads

Immersive Narrative

Implementation

Implementing Blaster Behavior

Implementing Player Data and Purchasing Systems

Importing PBR Textures

Importing into Studio

Improving Performance

In Blender

In-Experience Asset Creation

In-Experience Tools

In-Experience UI Containers

In-Game Sounds

In Studio

Input

Input and Camera

Installation and Setup

Instance Attributes

Instance Streaming

Intellectual Property

Interactive Buttons

Interfaces on Parts

Intermediate Gameplay

Introduction to Scripting

Intro to Arrays

Intro to Dictionaries

Intro to Digital Civility

Intro to Digital Safety

Intro to For Loops

Intro to Game Design and Coding

Intro to If Statements

Intro to Module Scripts

Intro to Roblox

Inventory

Inverse Kinematics

Invite Friends

Invite Friends to Play

Island Terrain

Island of Move

Labels

Language Codes

Laser Traps with Beams

Layered Clothing

Layout and Appearance

Layout and Design

Leaderboards

Legacy Chat System

Libraries

Light Sources

Lighting with Props

Lights and Polish

LineForce

LinearVelocity

List of Roblox Educators

LiveOps Essentials

LiveOps Planning

Loading Screens

Localization

Localizing with Scripting

Looping Animations

Looping through Arrays

Loops

Luau Reference

Main Design Requirements

Make Final Touches

Making Changes to Arrays

Making Mesh Watertight

Making an Explosion

Managing

Managing Players

Mansion of Wonder

Manually Editing Localization Table

Marketing Materials

Marketplace Fees and Commissions

Marketplace Overview

Marketplace Policy

Material Generator

Materializing the World

Materials

Mechanical Constraints

Memory Stores

Memory Usage

Merch Booth

Meshes

Messaging

Metatables

MicroProfiler

Migrating to In-Experience Text Chat

Minimap System

Mobile

Model Tab

Modeling

Modeling Specifications

Models

Moderation

Modifying Outer Cage

Monetization

Monetization Foundations

Monitoring

Monitoring Performance

Moods

Mouse and Keyboard

Mover Constraints

Moving the Body

Multi-Threading

Multiple Conditions with Else/If

Multiple Parameters and Arguments

NPC Kit

Name and Health Display

Native Code Generation

Nesting Loops

Network Ownership

Next Steps

NoCollision

Nominating for the Discover Page

Numbers

OAuth 2.0

Object Properties

Observability

On-Screen UI Containers

Onboarding

Onboarding Techniques

Opening the Template

Operators

Optimize Your Experience

Organizing Code

Output Window

PBR Material References

PBR Textures (Optional)

Packages

Paid Access

Pairs and iPairs

Parameters Practice - Buttons

Parents and Children

Particle Emitters

Parts

Passes

Pathfinding

Patterns

Per-Partition Limits

Performance

Performance Optimization

Photo Booth

Physically-based Rendering (PBR)

Physics

Pickup System

Pivot Tools

Place Publishing

Plane

Planning for Educational Settings

Plant Reference Project

Platform Overview

Player Invite Prompts

Player UI

Players

Playing Background Music

Playing on Roblox

Playtest the Map

Plugins Tab

Policies and Guidelines

Positioning and Sizing

Post-Processing Effects

Prismatic

Private Servers

Products

Profile Card

Project Cleanup

Project Setup

Projects

Promotion

Properties Window

Properties and Attributes

Prototyping

Proximity Prompts

Publishing

Publishing Eyebrows and Eyelashes

Publishing to Marketplace

Quest Design

Queue

Queues

Quick Access Tools

R6 to R15 Adapter

Randomized Virtual Items Policy

Raycasting

Real-Time

Recent Releases

Record and Display Player Data

Reference Assets

Reference Files

Registration

Release Notes for 624

Release Notes for 625

Release Notes for 626

Release Notes for 627

Release Notes for 628

Release Notes for 629

Release Notes for 630

Release Notes for 631

Release Notes for 632

Remote

Removing Extra Bones

Repeating Code with while Loops

Retention

Returning Values From Tables

Reusing Code

Rich Text Markup

Rig Builder

Rigging

Rigging a Humanoid Model

Rigging a Humanoid Model (Blender)

Rigging a Simple Mesh (Blender)

Rigging and Skinning

Rights Manager

Right to Erasure Requests

Rigid

Rigid Accessories

Roblox Blender Plugin

Roblox Connect Project

Roblox Developer 101

Roblox Studio

Roblox Studio Basics

Roblox Units

Roblox User Base

Roblox for AP CSP

Roblox for Unity Developers

Roblox for Unreal Developers

Rope

Running Classrooms

Running the Game

Sample App

Save and Publish

Save by Publishing

Saving Data

Scavenger Hunt

Scheduler

Scope

Scoring Points

Script Editor

Script Profiler

Script Tab

Script an Upgrade Button

Scripting

Scripting Avatar Animations

Scripts

Sculpting

Sculpting Detail

Sculpting Terrain

Season Pass Design

Security Tactics and Cheat Mitigation

Selfie Mode

Selling Items

Selling on the Creator Store

Selling your Accessory

Services

Setting Up Mesh

Setting Up Studio

Setting Up a Roblox Classroom

Setting Up a Team

Sharing Your Speeders

Skinning a Humanoid Model

Skinning a Humanoid Model (Blender)

Skinning a Simple Mesh (Blender)

Skyboxes

Sleep System

Snap to Grid

Social Interactions

Solid Modeling

Sorted Map

Sound

Sound Design

Spatial Data

Spatial Voice

Spawn With Friends

Spawning and Respawning

Specifications

Sponsoring Experiences

Sponsoring Items

Spring

Stacks

Start Coding

Story Games

Streaming

Streaming in Immersion

Strings

Studio

Studio Interface

Studio Setup

Studio Shortcuts

Studio Testing Modes

Subscription Design

Subscriptions

Supporting Systems

Surface Art

Tables

Tag Table

Take Flight

Talent Hub Developer Safety

Task Scheduler

Teaching Remotely

Teams

Technical Overview

Technical Specifications

Teleporting

Template Files

Templates

Terrain

Terrain Editor

Terrain Tools

Test Tab

Test and Play

Test and Save

Testing

Testing Characters

Testing Poses

Test the Game

Test the Speeder

Text Chat

Text Filtering

Text Input

Texture Generator

Texture Painting

Texture Painting Setup

Texture Specifications

Textures and Decals

Texturing

Texturing Eyes

Texturing Face

The Mystery of Duvall Drive

The Storm

Third-Party Analytics Services

Third-Party Software

Timed Bridge For Loops

Timers and Events

Tips and Settings

Toolbox

Tools

Torque

TorsionSpring

Trails

Translating Dynamic Content

Translating Experience Page Information

Translating In-Experience Content

Trimming Clothing Shape

Tuples

Type Checking

Type Coercion

Types

Types and Locations

UI Animation

UI and UX

Unit Lessons

Universal

Uploading and Publishing

Uploading your Asset

User Advertisements

User Interface

User Interfaces

Userdata

Using Animations

Using Heads in Studio

Using Information with Parameters

Using MicroProfiler

Using Particles for Actions

Using Particles for Explosions

Using Studio's 3D Importer

Using Textures

Using the Accessory Fitting Tool

VR Guidelines

Validation Tool

Variables

Variables & Objects

VectorForce

Verifying Attachments

Video Assets

Video Frames

View Tab

Weapons Kit

Webhook Notifications

Weld

Working With Translators

Working in Teams

Writing the Story

Xbox Guidelines

AppLifecycleObserverService

Summary

Properties

Methods

Events

Properties

Methods

Events