UI

Connect Unity UI controls to values - in both directions.

UI components keep a Unity UI control and a value in sync. Interactive controls (toggles, sliders, input fields, the color picker) write to the value when the player uses them and follow the value when something else changes it - so two menus bound to the same value always agree, and a synchronized value updates everybody’s UI.

Use the prefabs

Every UI component ships as a ready-made prefab under Runtime/Prefabs/Local Values/UI and Runtime/Prefabs/Synchronized Values/UI. Drop one onto a world space canvas, reference your value and you are done.

Building a control yourself? Interactive controls need the Unity UI event wired back to the component, because Udon cannot subscribe to UI events at runtime:

Control	Unity event	Call
Toggle	`On Value Changed`	`UdonBehaviour.SendCustomEvent("_OnValueChanged")`
Slider	`On Value Changed`	`UdonBehaviour.SendCustomEvent("_OnValueChanged")`
TMP Input Field	`On Value Changed`	`UdonBehaviour.SendCustomEvent("_OnValueChanged")`
VRC URL Input Field	`On Value Changed`	`UdonBehaviour.SendCustomEvent("_OnValueChanged")`
Button (Toggle Button)	`On Click`	`UdonBehaviour.SendCustomEvent("_Toggle")`

Your canvas needs a VRC Ui Shape component and must be on a layer players can interact with (e.g. Default), otherwise the controls won’t respond to VRChat’s laser pointer.