# @ohos.app.ability.FenceExtensionAbility (FenceExtensionAbility)

The **FenceExtensionAbility** class provides geofence-related capabilities. It is inherited from the **ExtensionAbility** class.

> **NOTE**
>
> The initial APIs of this module are supported since API version 14. Newly added APIs will be marked with a superscript to indicate their earliest API version.
> The APIs of this module can be used only in the stage model. 

## Modules to Import

```ts
import FenceExtensionAbility from '@kit.LocationKit';
```

## Attributes

**System capability**: SystemCapability.Location.Location.Geofence

| Name| Type| Readable| Writable| Description|
| -------- | -------- | -------- | -------- | -------- |
| context | [FenceExtensionContext](js-apis-app-ability-FenceExtensionContext-sys.md) | Yes| No| Context of the Geofence service.|

## FenceExtensionAbility.onFenceStatusChange

onFenceStatusChange(transition: geoLocationManager.GeofenceTransition, additions: Record<string, string>): void;

Represents the callback triggered when a geofence status change event is received. Service processing is then performed based on the event type and data.

**System capability**: SystemCapability.Location.Location.Geofence

**Parameters**
| Name|  Type| Mandatory | Description |
| ------------ | ------------ | ------------ | ------------ |
|  transition |  [geoLocationManager.GeofenceTransition](js-apis-geoLocationManager.md#geofencetransition12) |  Yes| Geofence transition information, including the geofence ID and geofence event. |
| additions  | Record<string, string>  | Yes | Additional information. |

**Example**

```ts
import { FenceExtensionAbility, geoLocationManager } from '@kit.LocationKit';
import { notificationManager } from '@kit.NotificationKit';
import { wantAgent } from '@kit.AbilityKit';

export default class MyFenceExtensionAbility extends FenceExtensionAbility {
  async onFenceStatusChange(transition: geoLocationManager.GeofenceTransition,
    additions: Record<string, string>): void {
    // Receive the geofence status change event and process the service logic.
    hilog.info(0x0000, "TAG",
      `on geofence transition,id:${transition.geofenceId},event:${transition.transitionEvent},additions:${JSON.stringify(additions)}`);

    // Send a geofence notification.
    let wantAgentInfo: wantAgent.WantAgentInfo = {
      wants: [
        {
          bundleName: 'com.example.myapplication',
          abilityName: 'EntryAbility',
          parameters:
          {
            "geofenceId": transition?.geofenceId,
            "transitionEvent": transition?.transitionEvent,
          }
        } as Want
      ],
      actionType: wantAgent.OperationType.START_ABILITY,
      requestCode: 100
    };
    let wantAgentMy = await wantAgent.getWantAgent(wantAgentInfo);
    let notificationRequest: notificationManager.NotificationRequest = {
      id: 1,
      content: {
        notificationContentType: notificationManager.ContentType.NOTIFICATION_CONTENT_BASIC_TEXT,
        normal: {
          title: "Geofence Notification",
          text: `on geofence transition,id:${transition.geofenceId},event:${transition.transitionEvent},additions:${JSON.stringify(additions)}`,
        }
      },
      notificationSlotType: notificationManager.SlotType.SOCIAL_COMMUNICATION,
      wantAgent: wantAgentMy
    };
    notificationManager.publish(notificationRequest);
  }
}

```
## FenceExtensionAbility.onDestroy

onDestroy(): void;

Represents the callback triggered when a **FenceExtensionAbility** destruction event is received.

**System capability**: SystemCapability.Location.Location.Geofence

**Example**

```ts
import { FenceExtensionAbility } from '@kit.LocationKit';

class MyFenceExtensionAbility extends FenceExtensionAbility {
  onDestroy(): void {
    // Process the FenceExtensionAbility destruction event.
    hilog.info(0x0000, "TAG", `on ability destroy`);
  }
}

```