# Screen Lock Management


> ![icon-note.gif](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 screenlock from '@ohos.screenLock';
```


## screenlock.isScreenLocked

isScreenLocked(callback: AsyncCallback<boolean>): void

Checks whether the screen is locked. This method uses an asynchronous callback to return the result.

**System capability**: SystemCapability.MiscServices.ScreenLock

- Parameters
    | Name | Type | Mandatory | Description |
  | -------- | -------- | -------- | -------- |
  | callback | AsyncCallback<boolean> | Yes | Callback used to return the result. If **true** is returned, the screen is locked. If **false** is returned, the screen is not locked. |

- Example
  
  ```
  screenlock.isScreenLocked((err, data)=>{      
     if (err) {
          console.error('isScreenLocked callback error -> ${JSON.stringify(err)}');
          return;    
     }
     console.info('isScreenLocked callback success data -> ${JSON.stringify(data)}');
  });
  ```


## screenlock.isScreenLocked

isScreenLocked(): Promise<boolean>

Checks whether the screen is locked. This method uses a promise to return the result.

**System capability**: SystemCapability.MiscServices.ScreenLock

- Return Values
    | Type | Description |
  | -------- | -------- |
  | Promise<boolean> | Promise used to return the result. |

- Example
  
  ```
  screenlock.isScreenLocked().then((data) => {
      console.log('isScreenLocked success: data -> ${JSON.stringify(data)}');
  }).catch((err) => {
      console.error('isScreenLocked fail, promise: err -> ${JSON.stringify(err)}');
  });
  ```


## screenlock.isSecureMode

isSecureMode(callback: AsyncCallback<boolean>): void


Checks whether a device is in secure mode. This method uses an asynchronous callback to return the result.


**System capability**: SystemCapability.MiscServices.ScreenLock


- Parameters
    | Name | Type | Mandatory | Description |
  | -------- | -------- | -------- | -------- |
  | callback | AsyncCallback<boolean> | Yes | Callback used to return the result. If **true** is returned, the device is in secure mode. If **false** is returned, the device is not in secure mode. |

- Example
  
  ```
  screenlock.isSecureMode((err, data)=>{      
     if (err) {
          console.error('isSecureMode callback error -> ${JSON.stringify(err)}');
          return;    
     }
     console.info('isSecureMode callback success data -> ${JSON.stringify(err)}');
  });
  ```


## screenlock.isSecureMode

isSecureMode(): Promise<boolean>

Checks whether a device is in secure mode. This method uses a promise to return the result.

**System capability**: SystemCapability.MiscServices.ScreenLock

- Return Values
    | Type | Description |
  | -------- | -------- |
  | Promise<boolean> | Promise used to return the result. |

- Example
  
  ```
  screenlock.isSecureMode().then((data) => {
      console.log('isSecureMode success: data->${JSON.stringify(data)}');
  }).catch((err) => {
      console.error('isSecureMode fail, promise: err->${JSON.stringify(err)}');
  });
  ```


## screenlock.unlockScreen

unlockScreen(callback: AsyncCallback<void>): void


Unlocks the screen. This method uses an asynchronous callback to return the result.


**System capability**: SystemCapability.MiscServices.ScreenLock


- Parameters
    | Name | Type | Mandatory | Description |
  | -------- | -------- | -------- | -------- |
  | callback | AsyncCallback<void> | Yes | Callback function. If the callback fails, an error message is returned. |

- Example
  
  ```
  screenlock.unlockScreen((err)=>{      
     if (err) {
          console.error('unlockScreen callback error -> ${JSON.stringify(err)}');
          return;    
     }
     console.info('unlockScreen callback success');
  });
  ```


## screenlock.unlockScreen

unlockScreen(): Promise<void>

Unlocks the screen. This method uses a promise to return the result.

**System capability**: SystemCapability.MiscServices.ScreenLock

- Return Values
    | Type | Description |
  | -------- | -------- |
  | Promise<void> | Promise used to return the result. |

- Example
  
  ```
  screenlock.unlockScreen().then(() => {
      console.log('unlockScreen success');
  }).catch((err) => {
      console.error('unlockScreen fail, promise: err->${JSON.stringify(err)}');
  });
  ```