harmony 鸿蒙@ohos.app.ability.ApplicationStateChangeCallback (应用前后台状态变化监听器)

2025-06-12
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@ohos.app.ability.ApplicationStateChangeCallback (应用前后台状态变化监听器)

ApplicationStateChangeCallback模块提供应用上下文ApplicationContext对当前应用前后台变化监听回调的能力。

说明：

本模块首批接口从API version 10 开始支持。后续版本的新增接口，采用上角标单独标记接口的起始版本。

本模块接口仅可在Stage模型下使用。

导入模块

import { ApplicationStateChangeCallback } from '@kit.AbilityKit';

ApplicationStateChangeCallback.onApplicationForeground

onApplicationForeground(): void

注册当前应用前后台变化的监听后，在当前应用从后台切换到前台时触发回调。

原子化服务API：从API version 11开始，该接口支持在原子化服务中使用。

系统能力：SystemCapability.Ability.AbilityRuntime.AbilityCore

示例：

参见onApplicationBackground。

ApplicationStateChangeCallback.onApplicationBackground

onApplicationBackground(): void

注册当前应用前后台变化的监听后，在当前应用从前台切换到后台时触发回调。

原子化服务API：从API version 11开始，该接口支持在原子化服务中使用。

系统能力：SystemCapability.Ability.AbilityRuntime.AbilityCore

示例：

import { UIAbility, ApplicationStateChangeCallback } from '@kit.AbilityKit';
import { BusinessError } from '@kit.BasicServicesKit';

let applicationStateChangeCallback: ApplicationStateChangeCallback = {
  onApplicationForeground() {
    console.info('applicationStateChangeCallback onApplicationForeground');
  },
  onApplicationBackground() {
    console.info('applicationStateChangeCallback onApplicationBackground');
  }
};

export default class MyAbility extends UIAbility {
  onCreate() {
    console.log('MyAbility onCreate');
    // 1.获取applicationContext
    let applicationContext = this.context.getApplicationContext();
    try {
      // 2.通过applicationContext注册应用前后台状态监听
      if (applicationContext != undefined) {
        applicationContext.on('applicationStateChange', applicationStateChangeCallback);
      }
    } catch (paramError) {
      console.error(`error: ${(paramError as BusinessError).code}, ${(paramError as BusinessError).message}`);
    }
    console.log('Register applicationStateChangeCallback');
  }
  onDestroy() {
    let applicationContext = this.context.getApplicationContext();
    try {
      // 1.通过applicationContext解除注册应用前后台状态监听
      if (applicationContext != undefined) {
        applicationContext.off('applicationStateChange', applicationStateChangeCallback);
      } 
    } catch (paramError) {
      console.error(`error: ${(paramError as BusinessError).code}, ${(paramError as BusinessError).message}`);
    }
  }
}