Triggers when a UserEvent is raised.

Note: See this article for a more complete explanation of user events.

By default, OnUserEvent will only listen for events that are declared in one of its ancestor nodes. If you want to listen for events coming from anywhere, set the Filter property to Global.

OnUserEvent also lets you attach a JavaScript handler to the event.

<OnUserEvent EventName="myEvent" Handler="{myHandler}" />

The handler function is called with the arguments that were passed with the event as a plain JavaScript object.


This example defines a UserEvent and triggers it when the panel is clicked:

<Panel ux:Name="panel" Color="Blue">
    <UserEvent Name="myEvent"/>
    <OnUserEvent EventName="myEvent">
        <Change panel.Color="Red" DurationBack="0.5" />
        <RaiseUserEvent EventName="myEvent" />

This example illustrates how you can read the arguments that were passed with the event from a JavaScript handler.

<UserEvent ux:Name="myEvent" />

<Panel Color="#123">
        <RaiseUserEvent EventName="myEvent">
            <UserEventArg Name="myArgument" StringValue="Some value" />

<OnUserEvent EventName="myEvent" Handler="{eventHandler}" />

    function eventHandler(args) {
        console.log("myEvent raised with argument 'myArgument': " + args.myArgument);

    module.exports = { eventHandler: eventHandler };


Fuse.UserEvents 1.9.0

Interface of OnUserEvent

Inherited from Trigger

BackwardAnimation : TriggerAnimation ux

Specifies an explicit backward animation instead of using the implied backward animation of the animators involved. Be aware that actions are not part of the animation.

CrossFadeDuration : double ux

If there is a transition between forward/backward playback and two timeilnes are being used (implicit or explicit) this specifies the cross-fade time.

Deactivate uno

Deactivates the trigger (target progress of 0).

Pulse uno

Plays the trigger to progress 1 then back to 0.

RequireLayout(Visual) uno

Indicates the trigger is bound to the layout of a visual. This will keep the trigger in Bypass mode until after the first layout of the element is obtained. This is required since layout does not happen in the same root grouping/update phase as the creation of the element, yet not having a layout should qualify as part of the rooting period.

Inherited from NodeGroupBase

Nodes : IList of Node ux

Nodes to add to the Parent when this trigger is any non-deactivated state (Progress > 0)

Inherited from Node

ContextParent : Node uno

The context parent is the semantic parent of this node. It is where non-UI structure should be resolved, like looking for the DataContext, a Navigation, or other semantic item.

FindNodeByName(Selector, Predicate<Node> (Node)) : Node uno

Finds the first node with a given name that satisfies the given acceptor. The serach algorithm works as follows: Nodes in the subtree are matched first, then it matches the nodes in the subtrees ofthe ancestor nodes by turn all the way to the root. If no matching node is found, the function returns null.

IsRootingStarted : bool uno

Whether rooting of this node has started. Note that even if this property returns true, rooting may not yet be completed for the node. See also IsRootingCompleted.

Name : Selector ux

Run-time name of the node. This property is automatically set using the ux:Name attribute.

OnRooted uno

If you override OnRooted you must call base.OnRooted() first in your derived class. No other processing should happen first, otherwise you might end up in an undefined state.

Inherited from PropertyObject

Inherited from object

Attached UX Attributes

GlobalKey (attached by Resource) : string ux

The ux:Global attribute creates a global resource that is accessible everywhere in UX markup.

Implemented Interfaces

IScriptObject uno

Interface for objects that can have a script engine representation