@ohos.resourceschedule.backgroundTaskManager (Background Task Management) (System API)

The backgroundTaskManager module provides APIs to request background tasks. You can use the APIs to request transient tasks, continuous tasks, or efficiency resources to prevent the application process from being terminated or suspended when your application is switched to the background.

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.

This topic describes only system APIs provided by the module. For details about its public APIs, see @ohos.resourceschedule.backgroundTaskManager (Background Task Management).

Modules to Import

import backgroundTaskManager from '@ohos.resourceschedule.backgroundTaskManager';

backgroundTaskManager.applyEfficiencyResources

applyEfficiencyResources(request: EfficiencyResourcesRequest): void

Requests efficiency resources.

System capability: SystemCapability.ResourceSchedule.BackgroundTaskManager.EfficiencyResourcesApply

System API: This is a system API.

Parameters

Name	Type	Mandatory	Description
request	EfficiencyResourcesRequest	Yes	Necessary information carried in the request, including the resource type and timeout interval.

Error codes

For details about the error codes, see backgroundTaskManager Error Codes.

ID	Error Message
9800001	Memory operation failed.
9800002	Parcel operation failed.
9800003	Inner transact failed.
9800004	System service operation failed.
18700001	Caller information verification failed.

Example

import { BusinessError } from '@ohos.base';

let request: backgroundTaskManager.EfficiencyResourcesRequest = {
    resourceTypes: backgroundTaskManager.ResourceType.CPU,
    isApply: true,
    timeOut: 0,
    reason: "apply",
    isPersist: true,
    isProcess: false,
};
try {
    backgroundTaskManager.applyEfficiencyResources(request);
    console.info("applyEfficiencyResources success. ");
} catch (error) {
    console.error(`applyEfficiencyResources failed. code is ${(error as BusinessError).code} message is ${(error as BusinessError).message}`);
}

backgroundTaskManager.resetAllEfficiencyResources

resetAllEfficiencyResources(): void

Releases all efficiency resources.

System capability: SystemCapability.ResourceSchedule.BackgroundTaskManager.EfficiencyResourcesApply

System API: This is a system API.

Error codes

For details about the error codes, see backgroundTaskManager Error Codes.

ID	Error Message
9800001	Memory operation failed.
9800002	Parcel operation failed.
9800003	Inner transact failed.
9800004	System service operation failed.
18700001	Caller information verification failed.

Example

import { BusinessError } from '@ohos.base';

try {
    backgroundTaskManager.resetAllEfficiencyResources();
} catch (error) {
    console.error(`resetAllEfficiencyResources failed. code is ${(error as BusinessError).code} message is ${(error as BusinessError).message}`);
}

BackgroundMode

Enumerates the continuous task modes.

System capability: SystemCapability.ResourceSchedule.BackgroundTaskManager.ContinuousTask

Name	Value	Description
WIFI_INTERACTION	7	WLAN-related. System API: This is a system API.
VOIP	8	Audio and video calls. System API: This is a system API.

EfficiencyResourcesRequest

Describes the parameters for requesting efficiency resources.

System capability: SystemCapability.ResourceSchedule.BackgroundTaskManager.EfficiencyResourcesApply

System API: This is a system API.

Name	Type	Mandatory	Description
resourceTypes	number	Yes	Type of the resource to request.
isApply	boolean	Yes	Whether the request is used to apply for resources. The value true means that the request is used to apply for resources, and false means that the request is used to release resources.
timeOut	number	Yes	Duration for which the resource will be used, in milliseconds.
isPersist	boolean	No	Whether the resource is permanently held. The default value is false. The value true means that the resource is permanently held, and false means the resource is held within a given period of time.
isProcess	boolean	No	Whether the request is initiated by a process. The default value is false. The value true means that the request is initiated by a process, and false means that the request is initiated by an application.
reason	string	Yes	Reason for requesting the resource.

ResourceType

Enumerates the efficiency resource types.

System capability: SystemCapability.ResourceSchedule.BackgroundTaskManager.EfficiencyResourcesApply

System API: This is a system API.

Name	Value	Description
CPU	1	CPU resource. Such type of resource prevents an application from being suspended.
COMMON_EVENT	2	Common event resource. Such type of resource ensures that an application in the suspended state can receive common events.
TIMER	4	Timer resource. Such type of resource ensures that an application in the suspended state can be woken up by system timers.
WORK_SCHEDULER	8	Deferred task resource. Such type of resource provides a loose control policy for an application.
BLUETOOTH	16	Bluetooth resource. Such type of resource ensures that an application in the suspended state can be woken up by Bluetooth-related events.
GPS	32	GPS resource. Such type of resource ensures that an application in the suspended state can be woken up by GPS-related events.
AUDIO	64	Audio resource. Such type of resource prevents an application from being suspended when the application has an audio being played.
RUNNING_LOCK¹⁰⁺	128	RUNNING_LOCK resources are not proxied when the application is suspended.
SENSOR¹⁰⁺	256	Sensor callbacks are not intercepted.