RegisterCallback
Adds an event handler to the instance.
Read time 3 minutesLast updated 6 days ago
Definition
- Type: Method
- Namespace: UnityEngine.UIElements
- Assembly: UnityEngine.UIElementsModule
RegisterCallback<T>(EventCallback<T>, TrickleDown)
Adds an event handler to the instance.
public void RegisterCallback<TEventType>(EventCallback<TEventType> callback, TrickleDown useTrickleDown = TrickleDown.NoTrickleDown) where TEventType : EventBase<TEventType>, new()
Parameters
The event handler to add. If the handler is null, this method throws an exception.
By default, this callback is called during the BubbleUp phase. Pass to call this callback during the TrickleDown phase.
TrickleDown.TrickleDownRemarks
If the event handler is already registered for the same phase (either TrickleDown or BubbleUp), this method has no effect.
Refer to the Handle event callbacks and value changes manual page for more information and examples.
Additional Resources: PropagationPhase
RegisterCallback<T, U>(EventCallback<T, T>, T, TrickleDown)
Adds an event handler to the instance.
public void RegisterCallback<TEventType, TUserArgsType>(EventCallback<TEventType, TUserArgsType> callback, TUserArgsType userArgs, TrickleDown useTrickleDown = TrickleDown.NoTrickleDown) where TEventType : EventBase<TEventType>, new()
Parameters
The event handler to add. If the handler is null, this method throws an exception.
By default, this callback is called during the BubbleUp phase. Pass to call this callback during the TrickleDown phase.
TrickleDown.TrickleDownRemarks
If the event handler is already registered for the same phase (either TrickleDown or BubbleUp), this method has no effect.
Refer to the Handle event callbacks and value changes manual page for more information and examples.
Additional Resources: PropagationPhase
Examples
using UnityEngine;using UnityEngine.UIElements;[RequireComponent(typeof(UIDocument))]public class RegisterCallbackExample : MonoBehaviour{ void OnEnable() { var myClickableLabel = new Label("Click me"); myClickableLabel.RegisterCallback<PointerDownEvent, string>((ev, userArg) => { Debug.Log("Hello from " + userArg); }, gameObject.name); GetComponent<UIDocument>().rootVisualElement.Add(myClickableLabel); }}
RegisterCallback<T>(EventCallback<T>, CallbackOptions)
Adds an event handler to the instance.
public void RegisterCallback<TEventType>(EventCallback<TEventType> callback, CallbackOptions callbackOptions) where TEventType : EventBase<TEventType>, new()
Parameters
The event handler to add. If the handler is null, this method throws an exception.
Extra properties to set for the callback.
Remarks
If the event handler is already registered for the same phase (either TrickleDown or BubbleUp), this method has no effect.
Refer to the Handle event callbacks and value changes manual page for more information and examples.
Additional Resources: PropagationPhase
RegisterCallback<T, U>(EventCallback<T, T>, T, CallbackOptions)
Adds an event handler to the instance.
public void RegisterCallback<TEventType, TUserArgsType>(EventCallback<TEventType, TUserArgsType> callback, TUserArgsType userArgs, CallbackOptions callbackOptions) where TEventType : EventBase<TEventType>, new()
Parameters
The event handler to add. If the handler is null, this method throws an exception.
Extra properties to set for the callback.
Remarks
If the event handler is already registered for the same phase (either TrickleDown or BubbleUp), this method has no effect.
Refer to the Handle event callbacks and value changes manual page for more information and examples.
Additional Resources: PropagationPhase