How to: Detect User Idle Time or Inactivity

This topic shows how to create a procedure that will run if your Microsoft Access application does not detect any user input for a specified period of time. It involves creating a hidden form, DetectIdleTime, which keeps track of idle time.

Follow these steps to create the DetectIdleTime form.

1. Create a blank form that is not based on any table or query and name it DetectIdleTime.

2. Set the following form properties:

   Note

   The TimerInterval setting indicates how often (in milliseconds) the application checks for user inactivity. A setting of 1000 equals 1 second.

   Property	Value
   OnTimer	[Event Procedure]
   TimerInterval	1000

3. Enter the following code for the OnTimer property event procedure:

         Sub Form_Timer() 
            ' IDLEMINUTES determines how much idle time to wait for before 
            ' running the IdleTimeDetected subroutine. 
            Const IDLEMINUTES = 5 
   
            Static PrevControlName As String 
            Static PrevFormName As String 
            Static ExpiredTime 
   
            Dim ActiveFormName As String 
            Dim ActiveControlName As String 
            Dim ExpiredMinutes 
   
            On Error Resume Next 
   
            ' Get the active form and control name. 
   
            ActiveFormName = Screen.ActiveForm.Name 
            If Err Then 
               ActiveFormName = "No Active Form" 
               Err = 0 
            End If 
   
            ActiveControlName = Screen.ActiveControl.Name 
               If Err Then 
               ActiveControlName = "No Active Control" 
               Err = 0 
            End If 
   
            ' Record the current active names and reset ExpiredTime if: 
            '    1. They have not been recorded yet (code is running 
            '       for the first time). 
            '    2. The previous names are different than the current ones 
            '       (the user has done something different during the timer 
            '        interval). 
            If (PrevControlName = "") Or (PrevFormName = "") _ 
              Or (ActiveFormName <> PrevFormName) _ 
              Or (ActiveControlName <> PrevControlName) Then 
               PrevControlName = ActiveControlName 
               PrevFormName = ActiveFormName 
               ExpiredTime = 0 
            Else 
               ' ...otherwise the user was idle during the time interval, so 
               ' increment the total expired time. 
               ExpiredTime = ExpiredTime + Me.TimerInterval 
            End If 
   
            ' Does the total expired time exceed the IDLEMINUTES? 
            ExpiredMinutes = (ExpiredTime / 1000) / 60 
            If ExpiredMinutes >= IDLEMINUTES Then 
               ' ...if so, then reset the expired time to zero... 
               ExpiredTime = 0 
               ' ...and call the IdleTimeDetected subroutine. 
               IdleTimeDetected ExpiredMinutes 
            End If 
         End Sub
   

4. Create the following procedure in the form module:

         Sub IdleTimeDetected(ExpiredMinutes) 
            Dim Msg As String 
            Msg = "No user activity detected in the last " 
            Msg = Msg & ExpiredMinutes & " minute(s)!" 
            MsgBox Msg, 48 
         End Sub
   

To hide the DetectIdleTime form as it opens, set the WindowMode argument of the OpenForm method to acHidden.