B4J Question how to continue process

[jinyistudio]

Hi

how to slove system lag questtion !? My system will lag "interval ms" when i run this code !

public Sub test(interval As Int)
    Dim now As Long=DateTime.Now
    Do While True
        If (DateTime.Now-now)>interval Then
            Exit
        End If
    Loop
End Sub

 

[stanmiller]

This is called "busy waiting". You need to use a proper timer or sleep interval.

Busy waiting
https://en.wikipedia.org/wiki/Busy_waiting

I'll wait for another to jump in to give you an example in B4J syntax.

 

[Daestrum]

It would help if you explained why you are using the code, so we can post alternate ways to achieve the same effect without tying the main thread up.

 

[Erel]

You can also use CallSubPlus to run a sub after x milliseconds.

 

[jinyistudio]

sorry ! following is my correct code :

public Sub test(interval As Int) as int
   dim retn as int
   Dim now As Long=DateTime.Now
   Do While True
      if IsItRespone(data,20) then
         retn = 0 ' OK, I got a packet from RS-232
         exit
      else
        If (DateTime.Now-now)>interval Then
          retn = -1 ' NG, I haven't got a packet from RS-232
          exit
        End If
      End If
   
   Loop
   return retn
End Sub

 

[Erel]

Events will not be raised while the main thread is in the loop.