Scene

The Scene interface represents a scene in Home Assistant. When you define a field of type Scene in your SmartBean class and annotate it with @Entity, the framework automatically injects an object that lets you control the corresponding scene in Home Assistant.

@Entity("scene.cosy_light")
private Scene scene;

State

Scenes in Home Assistant maintain a state that represents the timestamp of their last activation. While this state might not be directly useful for automation logic, you can query it if needed using this method:

Method	Description
getStateAsString()	Returns the original state from the Home Assistant entity.

Attributes

The following attributes of a scene can be accessed through simple getter methods:

HA attribute	Method	Description
friendly_name	getFriendlyName()	Friendly name of the entity.
icon	getIcon()	Icon of the entity.

You can access any additional attributes that are not directly supported through the getAttributes() method.

Activate Scene

The Scene interface provides a turnOn() method to activate scenes. This method accepts an optional double parameter that specifies the transition duration in seconds. When no transition time is provided, the scene activates immediately.

public class ASampleBean implements SmartBean {

  @Entity("scene.cosy_light")
  private Scene scene;

  public void someBeanMethod() {
    scene.turnOn(1.5);
  }
}

Access Entities Programmatically

In addition to the annotation-based approach, you can programmatically access scenes using the getScene() method of the SmartBeans API. You might prefer this programmatic approach over annotations for example when the entity ID is dynamically generated through business logic and cannot be determined at compile time.

public class ASampleBean implements SmartBean {

  private SmartBeans sb;

  public void someBeanMethod() {
    Scene scene = sb.getScene("scene.cosy_light");
    scene.turnOn(5);
  }
}

note

For improved efficiency, it is recommended to cache entity objects as member variables rather than retrieving them repeatedly. Since the state and attributes of entity objects are cached internally, no additional backend communication is required for multiple state retrievals. Note that initial entity object creation always requires at least one request to the Home Assistant backend.