Android Question GMT time

[kepler]

Good evening,

I was wondering how I can get the universal GMT time from any android device.

I can extract the current date, and the time zone offset.

But what is the simpliest way of getting the GMT time in two strings, one with the date and the other with the time (24h format)?

Is the offset suposed to be added to the current time (that is, eastern regions have negative offsets)? But how can I subtract the offset from a date?...

Sorry for disturbing.

Kind regards,

Kepler

 

[eurojam]

did you read this post: https://www.b4x.com/android/forum/threads/how-to-calculate-get-gmt.11666/
don't know, if this will be the solution for you...but may be it helps...

 

[kepler]

Hi,

Thanks for the link. I've made the following test code:

Sub GetGMT As String()
   Dim s, d As String
   Dim l As Long
   s = DateTime.DateFormat
   DateTime.DateFormat = "dd/MM/yyyy HH:mm:ss"
   l = DateTime.Now
   d = DateTime.Date(l) & " GMT"
   DateTime.DateFormat = "dd/MM/yyyy HH:mm:ss z"
   Dim res As Int
   res = -Round((l - DateTime.DateParse(d))/3600000) 'offset in seconds
   DateTime.DateFormat = s
  
   res = res * 1000 'offset in miliseconds
  
   l = l + res
  
    Dim dt As String
    Dim dt2 As String
  
    DateTime.DateFormat = "dd.MM.yyyy"   
    dt = DateTime.Date(l) 'Date only
    DateTime.DateFormat = "HH.mm.ss"
    dt2 = DateTime.Date(l) 'Time only

    Dim res_data() As String
    res_data = Array As String (dt,dt2)
    Return res_data
  
End Sub

Is this right in your opinion?

Regards,

Kepler

 

[Mahares]

This looks more like what you want: the offset res in in hrs not sec

Sub GetGMT As String()
   Dim s, d As String
   Dim l As Long
   s = DateTime.DateFormat
   DateTime.DateFormat = "dd/MM/yyyy HH:mm:ss"
   l = DateTime.Now
   d = DateTime.Date(l) & " GMT"
   DateTime.DateFormat = "dd/MM/yyyy HH:mm:ss z"
   Dim res As Int
   res = -Round((l - DateTime.DateParse(d))/3600000) 'offset in hrs  :exple: -5
 
   l = l  - res * 1000 * 3600  'millisec

    Dim dt, dt2 As String
    DateTime.DateFormat = "dd.MM.yyyy"  
    dt = DateTime.Date(l) 'Date only
    DateTime.DateFormat = "HH.mm.ss"
    dt2 = DateTime.Date(l) 'Time only

    Dim res_data() As String
    res_data = Array As String (dt,dt2)
    Log(res_data(0) &  "   "  & res_data(1))  'returns GMT date and time: exple: 28.2.2016  01:30:56
    DateTime.DateFormat = s
    Return res_data
 End Sub

 

[kepler]

Hi,

You're right - I've noticed it a few hours ago. But I had no chance to come here and correct the posted code.

Thanks anyway

Kind regards,

Kepler

 

[Erel]

The simplest way is to set the time zone to 0 (it only sets the process time zone):

DateTime.SetTimeZone(0)

Log(DateTime.Time(DateTime.Now)) 'gmt

 

[LucaMs]

Note that using SetTimeZone(0) you'll get the device date converted to GMT, so, if the device date (time) is wrong the GMT will be wrong.

I think you should get the real GMT from the WEB.

 

[LucaMs]

I found a useful post; it's about UTC and MySql, not GTM, but I think it can be very useful (I don't know where I should post the link, on this site; some Code Snippets forum? B4J? )


http://stackoverflow.com/questions/19023978/should-mysql-have-its-timezone-set-to-utc