@ohos.app.ability.AbilityConstant (AbilityConstant)

AbilityConstant提供UIAbility相关的枚举，包括设置初次启动原因、上次退出原因、迁移结果、窗口类型等。

说明：

本模块首批接口从API version 9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 AbilityConstant from '@ohos.app.ability.AbilityConstant';

AbilityConstant.LaunchParam

启动参数。Ability启动时由系统自动传入，开发者无需修改。

元服务API： 从API version 11开始，该接口支持在元服务中使用。

系统能力：SystemCapability.Ability.AbilityRuntime.Core

AbilityConstant.LaunchReason

Ability初次启动原因，该类型为枚举，可配合UIAbility的onCreate(want, launchParam)方法根据launchParam.launchReason的不同类型执行相应操作。

系统能力：SystemCapability.Ability.AbilityRuntime.Core

示例：

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

class MyAbility extends UIAbility {
    onCreate(want: Want, launchParam: AbilityConstant.LaunchParam) {
        if (launchParam.launchReason === AbilityConstant.LaunchReason.START_ABILITY) {
            console.log('The ability has been started by the way of startAbility.');
        }
    }
}

AbilityConstant.LastExitReason

Ability上次退出原因，该类型为枚举，可配合UIAbility的onCreate(want, launchParam)方法根据launchParam.lastExitReason的不同类型执行相应操作。

系统能力：SystemCapability.Ability.AbilityRuntime.Core

示例：

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

class MyAbility extends UIAbility {
    onCreate(want: Want, launchParam: AbilityConstant.LaunchParam) {
        if (launchParam.lastExitReason === AbilityConstant.LastExitReason.APP_FREEZE) {
            console.log('The ability has exit last because the ability was not responding.');
        }
    }
}

AbilityConstant.OnContinueResult

Ability迁移结果，该类型为枚举，可配合UIAbility的onContinue(wantParam)方法进完成相应的返回。

元服务API： 从API version 11开始，该接口支持在元服务中使用。

系统能力：SystemCapability.Ability.AbilityRuntime.Core

示例：

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

class MyAbility extends UIAbility {
    onContinue(wantParam: Record<string, Object>) {
        return AbilityConstant.OnContinueResult.AGREE;
    }
}

AbilityConstant.MemoryLevel

内存级别，该类型为枚举，可配合UIAbility的onMemoryLevel(level)方法根据level执行不同内存级别的相应操作。

元服务API： 从API version 11开始，该接口支持在元服务中使用。

系统能力：以下各项对应的系统能力均为SystemCapability.Ability.AbilityRuntime.Core

示例：

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

class MyAbility extends UIAbility {
    onMemoryLevel(level: AbilityConstant.MemoryLevel) {
        if (level === AbilityConstant.MemoryLevel.MEMORY_LEVEL_CRITICAL) {
            console.log('The memory of device is critical, please release some memory.');
        }
    }
}

AbilityConstant.OnSaveResult

保存应用数据的结果，该类型为枚举，可配合UIAbility的onSaveState(reason, wantParam)方法完成相应的返回。

元服务API： 从API version 11开始，该接口支持在元服务中使用。

系统能力：以下各项对应的系统能力均为SystemCapability.Ability.AbilityRuntime.Core

示例：

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

class MyAbility extends UIAbility {
    onSaveState(reason: AbilityConstant.StateType, wantParam: Record<string, Object>) {
        return AbilityConstant.OnSaveResult.ALL_AGREE;
    }
}

AbilityConstant.StateType

保存应用数据场景原因，该类型为枚举，可配合UIAbility的onSaveState(reason, wantParam)方法根据reason的不同类型执行相应操作。

元服务API： 从API version 11开始，该接口支持在元服务中使用。

系统能力：以下各项对应的系统能力均为SystemCapability.Ability.AbilityRuntime.Core

示例：

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

class MyAbility extends UIAbility {
    onSaveState(reason: AbilityConstant.StateType, wantParam: Record<string, Object>) {
        if (reason === AbilityConstant.StateType.CONTINUATION) {
            console.log('Save the ability data when the ability continuation.');
        } 
        return AbilityConstant.OnSaveResult.ALL_AGREE;
    }
}

AbilityConstant.ContinueState¹⁰⁺

流转状态枚举值。用于表示当前应用任务流转的状态。可配合UIAbilityContext的setMissionContinueState方法进行设置。

元服务API： 从API version 11开始，该接口支持在元服务中使用。

系统能力：SystemCapability.Ability.AbilityRuntime.Core

示例：

import UIAbility from '@ohos.app.ability.UIAbility';
import Want from '@ohos.app.ability.Want';
import { BusinessError } from '@ohos.base';
import AbilityConstant from '@ohos.app.ability.AbilityConstant';

class MyAbility extends UIAbility {
  onCreate(want: Want, launchParam: AbilityConstant.LaunchParam) {
    this.context.setMissionContinueState(AbilityConstant.ContinueState.INACTIVE, (result: BusinessError) => {
      console.info(`setMissionContinueState: ${JSON.stringify(result)}`);
    });
  }
}