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

Class SetPropertyAction<T>

java.lang.Object
com.vaadin.flow.component.trigger.internal.Action
com.vaadin.flow.component.trigger.internal.SetPropertyAction<T>
Type Parameters:
T - the runtime type of the value to assign
All Implemented Interfaces:
Serializable
public class SetPropertyAction<T> extends Action
Assigns a value to a JavaScript property on a target element when the bound trigger fires. Pure client-side — no server round-trip.

Symmetric with PropertyInput: the same property name space (DOM/custom-element properties such as value, checked, disabled).

The value to assign can be either a literal (constant, serialised at build time) or an Action.Input that produces the value on the client when the trigger fires — for example, click.screenX() feeds the click's screen coordinate.

Common idioms:

  • Disable a button: new SetPropertyAction(button, "disabled", true)
  • Clear an input: new SetPropertyAction(input, "value", "")
  • Mirror a click coordinate: new SetPropertyAction(field, "value", click.screenX())
Server-side state is not updated by this action; the change 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:

  • Constructor Details

    • SetPropertyAction

      public SetPropertyAction(Component target, String propertyName, @Nullable T value)
      Creates an action that assigns the given literal value to the given JS property on target when the trigger fires. Passing null clears the property (renders target[prop] = null;).
      Parameters:
      target - the component whose root element to modify, not null
      propertyName - the JS property name, not null
      value - the value to assign — String, Boolean, Number, or any Jackson-serialisable object; may be null to emit a JS null (e.g. to clear an input's value)

    • SetPropertyAction

      public SetPropertyAction(Component target, String propertyName, Action.Input<? extends T> source)
      Creates an action that assigns the value produced by source to the given JS property on target when the trigger fires.
      Parameters:
      target - the component whose root element to modify, not null
      propertyName - the JS property name, not null
      source - input that produces the value to assign, not 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