1# @ohos.app.ability.ExtensionAbility (ExtensionAbility Base Class) 2<!--Kit: Ability Kit--> 3<!--Subsystem: Ability--> 4<!--Owner: @yewei0794--> 5<!--Designer: @jsjzju--> 6<!--Tester: @lixueqing513--> 7<!--Adviser: @huipeizi--> 8 9<!--Kit: Ability Kit--> 10<!--Subsystem: Ability--> 11<!--Owner: @yewei0794--> 12<!--Designer: @jsjzju--> 13<!--Tester: @lixueqing513--> 14 15ExtensionAbility is the base class for scenario-specific ExtensionAbilities. It inherits from [Ability](js-apis-app-ability-ability.md), with no property or method added. You cannot directly inherit from ExtensionAbility. For details about the inheritance relationship of each ability, see [Inheritance Relationship](./js-apis-app-ability-ability.md#ability-inheritance-relationship). 16 17> **NOTE** 18> 19> The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version. 20> 21> The APIs of this module can be used only in the stage model. 22 23## Modules to Import 24 25```ts 26import { ExtensionAbility } from '@kit.AbilityKit'; 27``` 28 29**Atomic service API**: This API can be used in atomic services since API version 11. 30 31**System capability**: SystemCapability.Ability.AbilityRuntime.AbilityCore 32