Introduction to PowerBuilder

HomePrevious Lesson: Deleting a Row from the DataWindow
Next Lesson: Sorting the Data

Saving Changes to the Database

// Object: cb_save in window w_product_master
// Event: Clicked
int lUserAnswer, lUpdateStatus
lUserAnswer = MessageBox("Update", &
                 "Apply Changes ?", Question!,YesNo!,2)
if lUserAnswer = 1 then 
   SetPointer( HourGlass!)
   lUpdateStatus = dw_product.Update()
   if lUpdateStatus = 1 then
      commit using SQLCA;
   else
      SetPointer( Arrow!) 
      RollBack using SQLCA;
      MessageBox("Update", "Error in update" + &
                  "Error Message: " + SQLCA.SqlErrText)
      return 0
   end if
end if
SetPointer( Arrow!)

The first thing we did was get a confirmation from the user regarding applying changes to the data. If the reply is positive, we call the Update() function and commit the changes, otherwise we ROLLBACK. While saving information to the database, it is a good idea to change the mouse pointer to an HourGlass, to indicate about the on going operation.

You should always keep the user informed about the things going on in an application. If a lengthy operation is in progress, you should give them an indication of it, otherwise, the user might think that things have gone wrong. The following table illustrates some of the general guidelines for lengthy operations:

Duration

Action

<= 4 seconds

Optional HourGlass cursor.

5 - 15 seconds

Display the HourGlass cursor.

15+ seconds

Display a message box and preferably an indicator for the progress.
HomePrevious Lesson: Deleting a Row from the DataWindow
Next Lesson: Sorting the Data