@ohos.app.ability.abilityLifecycleCallback (AbilityLifecycleCallback)

The AbilityLifecycleCallback module defines the callbacks to receive lifecycle changes of ApplicationContext.

NOTE

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.

The APIs of this module can be used only in the stage model.

Modules to Import

import AbilityLifecycleCallback from '@ohos.app.ability.AbilityLifecycleCallback';

AbilityLifecycleCallback.onAbilityCreate

onAbilityCreate(ability: UIAbility): void

Called when an ability is created.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

See Usage of AbilityLifecycleCallback.

AbilityLifecycleCallback.onWindowStageCreate

onWindowStageCreate(ability: UIAbility, windowStage: window.WindowStage): void

Called when the window stage of an ability is created.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

See Usage of AbilityLifecycleCallback.

AbilityLifecycleCallback.onWindowStageActive

onWindowStageActive(ability: UIAbility, windowStage: window.WindowStage): void

Called when the window stage of an ability gains focus.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

See Usage of AbilityLifecycleCallback.

AbilityLifecycleCallback.onWindowStageInactive

onWindowStageInactive(ability: UIAbility, windowStage: window.WindowStage): void

Called when the window stage of an ability loses focus.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

See Usage of AbilityLifecycleCallback.

AbilityLifecycleCallback.onWindowStageDestroy

onWindowStageDestroy(ability: UIAbility, windowStage: window.WindowStage): void

Called when the window stage of an ability is destroyed.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

See Usage of AbilityLifecycleCallback.

AbilityLifecycleCallback.onAbilityDestroy

onAbilityDestroy(ability: UIAbility): void

Called when an ability is destroyed.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

See Usage of AbilityLifecycleCallback.

AbilityLifecycleCallback.onAbilityForeground

onAbilityForeground(ability: UIAbility): void

Called when an ability is switched from the background to the foreground.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

See Usage of AbilityLifecycleCallback.

AbilityLifecycleCallback.onAbilityBackground

onAbilityBackground(ability: UIAbility): void

Called when an ability is switched from the foreground to the background.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

See Usage of AbilityLifecycleCallback.

AbilityLifecycleCallback.onAbilityContinue

onAbilityContinue(ability: UIAbility): void

Called when an ability is continued on another device.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

See Usage of AbilityLifecycleCallback.

Usage of AbilityLifecycleCallback

Example GlobalContext.ts Global context

// Construct a singleton object.
export class GlobalContext {
  private constructor() {}
  private static instance: GlobalContext;
  private _objects = new Map<string, Object>();

  public static getContext(): GlobalContext {
    if (!GlobalContext.instance) {
      GlobalContext.instance = new GlobalContext();
    }
    return GlobalContext.instance;
  }

  getObject(value: string): Object | undefined {
    return this._objects.get(value);
  }

  setObject(key: string, objectClass: Object): void {
    this._objects.set(key, objectClass);
  }
}

MyFirstAbility.ts First ability of the application

import AbilityLifecycleCallback from '@ohos.app.ability.AbilityLifecycleCallback';
import UIAbility from '@ohos.app.ability.UIAbility';

// Import GlobalContext. Use the actual path declared.
import { GlobalContext } from '../GlobalContext'

// Declare the ability lifecycle callbacks. A listener can be registered in applicationContext only after all the callbacks are configured.
let abilityLifecycleCallback: AbilityLifecycleCallback = {
    onAbilityCreate(ability){
        console.log('AbilityLifecycleCallback onAbilityCreate.');
    },
    onWindowStageCreate(ability, windowStage){
        console.log('AbilityLifecycleCallback onWindowStageCreate.');
    },
    onWindowStageActive(ability, windowStage){
        console.log('AbilityLifecycleCallback onWindowStageActive.');
    },
    onWindowStageInactive(ability, windowStage){
        console.log('AbilityLifecycleCallback onWindowStageInactive.');
    },
    onWindowStageDestroy(ability, windowStage){
        console.log('AbilityLifecycleCallback onWindowStageDestroy.');
    },
    onAbilityDestroy(ability){
        console.log('AbilityLifecycleCallback onAbilityDestroy.');
    },
    onAbilityForeground(ability){
        console.log('AbilityLifecycleCallback onAbilityForeground.');
    },
    onAbilityBackground(ability){
        console.log('AbilityLifecycleCallback onAbilityBackground.');
    },
    onAbilityContinue(ability){
        console.log('AbilityLifecycleCallback onAbilityContinue.');
    }
};

export default class MyFirstAbility extends UIAbility {
    onCreate() {
        console.log('MyAbilityStage onCreate');
        // 1. Obtain applicationContext through the context attribute.
        let applicationContext = this.context.getApplicationContext();
        // 2. Register the listener for the ability lifecycle changes through the applicationContext object.
        try {
            let lifecycleId = applicationContext.on('abilityLifecycle', abilityLifecycleCallback);
            GlobalContext.getContext().setObject("lifecycleId", lifecycleId);
            console.log(`registerAbilityLifecycleCallback lifecycleId: ${globalThis.lifecycleId}`);
        } catch (paramError) {
            console.error(`error: ${paramError.code}, ${paramError.message}`);
        }
    }
}

MySecondAbility.ts Second ability of the application

import UIAbility from '@ohos.app.ability.UIAbility';

// Import GlobalContext. Use the actual path declared.
import { GlobalContext } from '../GlobalContext'

export default class MySecondAbility extends UIAbility {
    onDestroy() {
        let applicationContext = this.context.getApplicationContext();
        let lifecycleId = GlobalContext.getContext().getObject("lifecycleId") as number;
        // 3. Deregister the listener for the ability lifecycle changes through the applicationContext object.
        applicationContext.off('abilityLifecycle', lifecycleId, (error) => {
            if (error && error.code !== 0) {
                console.error(`unregisterAbilityLifecycleCallback fail, error: ${JSON.stringify(error)}`);
            } else {
                console.log('unregisterAbilityLifecycleCallback success.');
            }
        });
    }
}