Update data showed in xBrowse

[vilian]

Hi guys,

I have a xBrowse where I show rows of a MySql Table. This module is opened in several computers at the same time and records are being modified.
What is the best way to keep updated the rows that are being shown in this xBrowse?

[karinha]

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   oBrw:Refresh(.T.) ??
 

Regards, saludos.

[vilian]

Karinha,
No my friend, oBrw:Refresh(.t) doesn't help.

The records are being modified in other computers, so i wanted to know if there is a way to be notified when the records need to be updated in xbrowse, because they were modified in others computers.

[Maurizio]

I use a refresh button with oBrw:oRs:Requery()

Maurizio

[vilian]

Than you Maurizio,

Nowaday, I'm doing like you.

[Marc Venken]

You could refresh the browse by using a timer (to read current data of changed items and if so refresh) so that changes on other computers will change the data on all computers.

[vilian]

Thank you Marc,

Yes, we're using a timer too. But I think xbrowser could have a method to Sync automatically all records that are been shown.

Look, not all the oRowset's records, just those that are visible right now in the xbrowser

[Marc Venken]

Maybe a autosync can be build .... I think from a earlier post from Mr. Rao that Xbrowse only updates the visible rows and not need to read the full rowset.
In that post we where talking about uptimised filters and indexes and Mr. Rao wanted to explain that in full theorie/praktic but due to time/work that item was not covered yet.

You probebli know that speed issues over LAN are gone once using FWH with Remote Desktop.

[vilian]

Yes, Something like an autosync would be great!

[Marc Venken]

Something to look into ??

viewtopic.php?f=3&t=36383

[vilian]

Yes,

But, there he is doing autosyng in the same computer and I need it in different computers.

[nageswaragunupudi]

No my friend, oBrw:Refresh(.t) doesn't help.

Obviously oBrw:Refresh() can not make oRs to read the records from the Server again.

Requerying frequently makes the application sluggish.

There is a less known method

Code: Select all  Expand view

oRowSet:Refresh()

This method refreshes only those records which are updated by other users on the network after the RowSet is updated last.
But this works only if the table contains a column that records "modified datetime"
Though it is very easy to create that kind of column using our library, I am sure most of users might not have created such column.

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oRowSet:Resync() // --? lChanged

This method reads the current record only from the server and updates.
Returns if the record is changed by other users.

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oRowSet:NetChanged( [RecNo], [@lDeleted] ) // -->lChanged

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oBrw:bChange := { || If( oRs:NetChanged(), oBrw:RefreshCurrent(), nil ) }

When we are navigating the browse, this will update the row from the server. Not all visible rows but the current row.

[vilian]

Thank you Mr Rao, your advices are always great!

oRowSet:Resync() // --? lChanged

Here, oRowSet:Resync() is always returning .T., even the record was not changed.

Do you think is possible to do an option to verify all visible record in the xBrowse and update only those that were changed?
Nowaday, I'm doing it by this way:

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LOCAL lTem:=.F.,nPos:=0,nRegAt := ::oTab:Recno()  
   
   DEFAULT bBloco := {|| .T.}  

   ::oTmr:DeActivate()
   ::oTab:Skip(::oLbx:nRowSel * (-1))
   DO WHILE nPos < ::oLbx:nDataRows .AND. .NOT. ::oTab:Eof()
      IF Eval(bBloco)
         lTem := .T.
         ::oTab:ReSync()
      ENDIF  
      nPos++
      ::oTab:Skip()
   ENDDO     ::oTab:GoTo(nRegAt)
   IF lTem
      ::oLbx:Refresh()
   ENDIF  
   ::oTmr:Activate()
 

But i believe it could be done better

[vilian]

I'm using Eval(bBloco) because I have some status where a record can't be modified anymore, so if he is in this status, i don´t need resync it.