Timer

The Timer module provides basic timer capabilities. You can use the APIs of this module to execute functions at the specified time.

NOTE

The initial APIs of this module are supported since API version 3. Newly added APIs will be marked with a superscript to indicate their earliest API version.

setTimeout

setTimeout(handler: Function | string, delay?: number, ...arguments: any[]): number

Sets a timer for the system to call a function after the timer goes off.

System capability: SystemCapability.ArkUI.ArkUI.Full

Parameters

Name Type Mandatory Description
handler Function | string Yes Function to be called after the timer goes off.
delay number No Number of milliseconds delayed before the execution. If this parameter is left empty, the default value 0 is used, which means that the execution starts immediately or as soon as possible.
...arguments Array<any> No Additional parameters to pass to the handler after the timer goes off.

Return value

Type Description
number Timer ID.

Example

export default {    
  setTimeOut() {        
    var timeoutID = setTimeout(function() {            
      console.log('delay 1s');
    }, 1000);    
  }
}

clearTimeout

clearTimeout(timeoutID: number): void

Cancels the timer created via setTimeout().

System capability: SystemCapability.ArkUI.ArkUI.Full

Parameters

Name Type Mandatory Description
timeoutID number Yes ID of the timer to cancel, which is returned by setTimeout()

Example

export default {    
  clearTimeOut() {        
    var timeoutID = setTimeout(function() {            
      console.log('do after 1s delay.');        
    }, 1000);        
    clearTimeout(timeoutID);    
  }
}

setInterval

setInterval(handler: Function | string, delay: number, ...arguments: any[]): number

Sets a repeating timer for the system to repeatedly call a function at a fixed interval.

System capability: SystemCapability.ArkUI.ArkUI.Full

Parameters

Name Type Mandatory Description
handler Function | string Yes Function to be called repeatedly.
delay number Yes Number of milliseconds delayed before the execution.
...arguments Array<any> No Additional parameters to pass to the handler after the timer goes off.

Return value

Type Description
number ID of the repeating timer.

Example

export default {    
  setInterval() {        
    var intervalID = setInterval(function() {            
      console.log('do very 1s.');        
    }, 1000);    
  }
}

clearInterval

clearInterval(intervalID: number): void

Cancels the repeating timer set via setInterval().

System capability: SystemCapability.ArkUI.ArkUI.Full

Parameters

Name Type Mandatory Description
intervalID number Yes ID of the repeating timer to cancel, which is returned by setInterval().

Example

export default {    
  clearInterval() {        
    var intervalID = setInterval(function() {
      console.log('do very 1s.');
    }, 1000);
    clearInterval(intervalID);
  }
}