# Running Lock >![](../../public_sys-resources/icon-note.gif) **NOTE:** >The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version. ## Modules to Import ``` import runninglock from '@ohos.runningLock'; ``` ## Required Permissions To request or use a running lock, you must declare the **ohos.permission.RUNNING\_LOCK** permission. ## RunningLockType Enumerates the types of running locks.

Description	Default Value	Description
BACKGROUND	1	A lock that prevents the system from hibernating.
PROXIMITY_SCREEN_CONTROL	2	A lock that determines whether to turn on or off the screen based on the distance away from the screen.

## runninglock.isRunningLockTypeSupported isRunningLockTypeSupported\(type: RunningLockType, callback: AsyncCallback\): void Checks whether a specified type of **RunningLock** is supported. This function uses an asynchronous callback to return the result. - Parameters

Name

Type

Mandatory

Description

type

RunningLockType

Yes

Type of the RunningLock object.

callback

AsyncCallback<boolean>

Yes

Callback used to obtain the return value.

The value true indicates that the specified type of RunningLock is supported, and value false indicates the opposite.

- Example ``` runningLock.isRunningLockTypeSupported(runningLock.RunningLockType.BACKGROUND, (error, supported) => { if (typeof error === "undefined") { console.info('BACKGROUND support status is ' + supported); } else { console.log('error: ' + error); } }) ``` ## runninglock.isRunningLockTypeSupported isRunningLockTypeSupported\(type: RunningLockType\): Promise Checks whether a specified type of **RunningLock** is supported. This function uses a promise to return the result. - Parameters

Name	Type	Mandatory	Description
type	RunningLockType	Yes	Type of the RunningLock object.

- Return values

Type	Description
Promise<boolean>	Promise used to asynchronously obtain the return value. The value true indicates that the specified type of RunningLock is supported, and value false indicates the opposite.

- Example ``` runningLock.isRunningLockTypeSupported(runningLock.RunningLockType.PROXIMITY_SCREEN_CONTROL) .then(supported => { console.info('PROXIMITY_SCREEN_CONTROL support status is ' + supported); }) .catch(error => { console.log('error: ' + error); }); ``` ## runninglock.createRunningLock createRunningLock\(name: string, type: RunningLockType, callback: AsyncCallback\): void Creates a **RunningLock** object. - Parameters

Name	Type	Mandatory	Description
name	string	Yes	Name of the RunningLock object.
type	RunningLockType	Yes	Type of the RunningLock object to be created.
callback	AsyncCallback<RunningLock>	Yes	Callback used to obtain the return value.

- Example ``` runningLock.createRunningLock("running_lock_test", runningLock.RunningLockType.BACKGROUND) .then(runninglock => { var used = runninglock.isUsed(); console.info('runninglock is used: ' + used); runninglock.lock(500); used = runninglock.isUsed(); console.info('after lock runninglock is used ' + used); }) .catch(error => { console.log('create runningLock test error: ' + error); }) ``` ## runninglock.createRunningLock createRunningLock\(name: string, type: RunningLockType\): Promise Creates a **RunningLock** object. - Parameters

Name	Type	Mandatory	Description
name	string	Yes	Name of the RunningLock object.
type	RunningLockType	Yes	Type of the RunningLock object to be created.

- Return values

Type	Description
Promise<RunningLock>	Promise used to asynchronously obtain the returned RunningLock object.

- Example ``` runningLock.createRunningLock("running_lock_test", runningLock.RunningLockType.BACKGROUND) .then(runninglock => { console.info('create runningLock success'); }) .catch(error => { console.log('create runningLock test error: ' + error); }) ``` ## RunningLock Defines a **RunningLock** object. ### lock lock\(timeout: number\): void Locks and holds a **RunningLock** object. - Parameters

Name	Type	Mandatory	Description
timeout	number	No	Duration for locking and holding the RunningLock object.

- Example ``` runningLock.createRunningLock("running_lock_test", runningLock.RunningLockType.BACKGROUND) .then(runningLock => { runningLock.lock(100) console.info('create runningLock success') }) .catch(error => { console.log('Lock runningLock test error: ' + error) }); ``` ### unlock unlock\(\): void Releases a **Runninglock** object. - Example ``` runningLock.createRunningLock("running_lock_test", runningLock.RunningLockType.BACKGROUND) .then(runningLock => { runningLock.unlock() console.info('unLock runningLock success') }) .catch(error => { console.log('unLock runningLock test error: ' + error) }); ``` ### isUsed isUsed\(\): boolean Checks the status of the **Runninglock** object. - Return values

Type	Description
boolean	Returns true if the Runninglock object is held; returns false if the Runninglock object is released.

- Example ``` runningLock.createRunningLock("running_lock_test", runningLock.RunningLockType.BACKGROUND) .then(runningLock => { var used = runningLock.isUsed() console.info('runningLock used status: ' + used) }) .catch(error => { console.log('runningLock isUsed test error: ' + error) }); ```