Package com.vaadin.flow.component.trigger.internal

Class CallMethodAction

java.lang.Object

com.vaadin.flow.component.trigger.internal.Action

com.vaadin.flow.component.trigger.internal.CallMethodAction

All Implemented Interfaces:

Serializable

public class CallMethodAction
extends Action

Calls a JavaScript method on a target element when the bound trigger fires. Pure client-side — no server round-trip; the method's return value is discarded.

Each argument is supplied as an Action.Input: a literal captured at build time, the current value of a DOM property, an event-scoped expression, or any other input. The rendered JS evaluates target[method](arg0, arg1, ...) where each argN is the input's value at the moment the trigger fires.

Common idioms:

• Focus an input on click: new CallMethodAction(input, "focus")
• Scroll an element into view: new CallMethodAction(panel, "scrollIntoView")
• Select all text: new CallMethodAction(field, "select")
• Click another element: new CallMethodAction(other, "click")
• Submit a form: new CallMethodAction(form, "requestSubmit")
• Play / pause a media element: new CallMethodAction(video, "play") / new CallMethodAction(video, "pause")
• Pass an options object built on the server: new CallMethodAction(panel, "scrollIntoView", new LiteralInput<>(Map.of("behavior", "smooth")))

For methods that return a Promise, the promise is created and dropped — the JS engine may log an unhandled-rejection warning if the promise rejects. Use PromiseAction based actions when you need to observe the outcome on the server.

Server-side state is not updated by this action; the call lives in the browser until the next sync from the client (if any).

For internal use only. May be renamed or removed in a future release.

See Also:

• Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class com.vaadin.flow.component.trigger.internal.Action

Action.Input<T>

Constructor Summary

Constructors

Constructor	Description
CallMethodAction(Component target, String methodName, Action.Input<?>... arguments)	Creates an action that, when the trigger fires, evaluates each input on the client and calls target[methodName](...) with those values.

Method Summary

Modifier and Type	Method	Description
protected JsFunction	toJs(Trigger trigger)	Builds the JsFunction that runs this action when the surrounding trigger fires.

Methods inherited from class com.vaadin.flow.component.trigger.internal.Action

applyTemporarily, warnIfNotVisible

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

CallMethodAction

public CallMethodAction(Component target,
 String methodName,
 Action.Input<?>... arguments)

Creates an action that, when the trigger fires, evaluates each input on the client and calls target[methodName](...) with those values.

Parameters:

target - the component on whose root element the method is invoked, not null

methodName - the JS method name (e.g. "focus", "scrollIntoView"), not null

arguments - inputs producing the method's positional arguments, in order; may be empty for a no-arg call. Neither the array nor any element may be null

Method Details

toJs

protected JsFunction toJs(Trigger trigger)

Description copied from class: Action

Builds the JsFunction that runs this action when the surrounding trigger fires. The returned function takes one runtime argument named event (declared by the framework when it composes the trigger handler); subclasses do not declare argument names themselves.

The body is one statement. To embed a value produced on the client, capture an Action.Input's JsFunction as a capture and invoke it inside the body as $N(event).

Specified by:

toJs in class Action

Parameters:

trigger - the surrounding trigger this render is for, not null

Returns:

the action's JS function, not null