This event is raised whenever the CE Forms Renderer wants to show a status line message, or error messages. The client program should show any status line data in its own status line. (The CE WinForm Renderer does not have a status line.) The client program can optionally show any errors itself.

If this event is not canceled, the CE Forms Renderer shows any errors, but is unable to show any status messages as forms do not have status lines.

To intercept this event, the client must write an event handler that matches the event Delegate:

StatusLineEventHandler().

To stop the CE Forms Renderer from showing error messages, set the BypassStatusHandling attribute of the CEFormEventArgs to true.

Example client event handler. (Visual Basic.NET)

 Sub SetStatusLine(ByVal sender As Object, ByVal e As PrototypeCEFormRenderer.CEFormEventArgs) 
Handles sampleSys.StatusLineEvent
      this.myStatusLine.Text = e.ObjStatus.Status
End Sub

The PreTransactionEvent is sent before the CE Forms Renderer calls the CE Transaction() method to send data to the host.

If intercepted, the client programmer can access the Session and Status objects, and manipulate the data, for example, to check the data the user has just entered, change that data if required, send one or more transactions to the host, etc..

You can alter the normal processing of the CE WinForm Renderer by the CEFormEventArgs object.

By setting the CancelFormRendering attribute of the CEFormEventArgs to true, the client programmer can stop the CE WinForm Renderer processing, and can take control of all processing.

By setting the BypassTransaction attribute of the CEFormEventArgs to true, the client programmer can tell the CE WinForm Renderer to skip the actual call to the CE Transaction() method, and to continue processing as if the CurrentIspec and Status objects have been returned from the host. (that is, the client programmer has manipulated the data in some way, and wants the CE WinForm Renderer to show the resulting form.)

If the client programmer bypasses the transaction method, the ReturnCode of the CEFormEventArgs should be set to an appropriate value. Refer to CEWindowsAPI.ResponseCodes class for values to use.

In General, this is 100 for an ok.

By setting/leaving both values as false, the CE WinForm Renderer carries on processsing as normal. (transmitting any new data the client programmer might have altered, to the host)

Example client event handler. (Visual Basic.NET)

 Sub ProcessPreTransactionEvent(ByVal sender As Object, ByVal e As PrototypeCEFormRenderer.CEFormEventArgs) 
Handles sampleSys.PreTransactionEvent
      Set CurrIspec = e.Session.CurrentIspec
      if CurrIspec.getFieldValue("ACTION") = "DRT231" then
            CurrIspec.setFieldValue("ACTION", "DRT123")
      end if
End Sub

The PostTransactionEvent is sent after the CE Forms Renderer has called the Transaction() method.

If intercepted, the client programmer can access the Session and Status objects, and manipulate the data. that is, check the data the host has just returned, change that data if required, send one or more transactions to the host, etc. You can alter the normal processing of the CE WinForm Renderer by the CEFormEventArgs object.

By setting the CancelFormRendering attribute to true, the client programmer can stop the CE WinForm Renderer processing, and can take control of all processing.

By setting/leaving the value as false, the CE WinForm Renderer carries on processsing as normal. (using any new data the client programmer might have altered)

The client programmer can examine or change the response code by accessing the ReturnCode attribute of CEFormEventArgs.

Example client event handler. (Visual Basic.NET)

Sub ProcessPostTransactionEvent(ByVal sender As Object, ByVal e As PrototypeCEFormRenderer.CEFormEventArgs) 
Handles sampleSys.PostTransactionEvent
      Set CurrIspec = e.Session.CurrentIspec
      if CurrIspec.Name = "CUST" then users of this client not allowed to see customer addresses.
            CurrIspec.setFieldValue("POSTADDR1", "Not Available")
            CurrIspec.setFieldValue("POSTADDR2", "")
            CurrIspec.setFieldValue("POSTADDR3", "")
      end if
End Sub

The LostFocusEvent must first be enabled before the client programmer can intercept the event. This enabling is required as raising extra events on every object of a form can degrade performance.

To enable this event, you need to set the CEFormRenderer.PropegateLostFocusEvent to true. This particular attribute can only be set in your clients code.

For example, sampleSys.PropagateLostFocusEvent = True

If intercepted, the client programmer can access the object that was sent the LostFocus event, and retrieve or alter the value of that item. The object that was sent in the LostFocus event is contained in the CEFormEventArgs SenderControl attribute.

While the Session and Status objects are available in this event, note that the individual GUI controls does not have set their values into the back end at this time. that is, if you want to check one fields value against another, you must interrogate the GUI controls directly. You cannot use the current ispec, as the values represented in it, and the GUI controls is likely to be different. (data is only transferred when a transmit is done)

The CEFormEventArgs is a class with a collection of objects that is passed in each event. Not all attributes of the CEFormEventArgs are populated for every event. Before using any particular attribute, check that it is used in the particular event that you are processing. Attribute

Objects

The CE WinForm Renderer has two objects that allow the user to control a session.

The Session object is a CEWindowsAPI.LINCEnvironment object. Using this object, the programmer can control the entire session, or just some parts.

The CE WinForm Renderer also has a Status object. This is a CEWindowsAPI.LINCStatus object, that the CE WinForm Renderer uses in all of its internal logic, that is, the Status objects have the results of all transactions performed by the CE Form Renderer.

For details of both these objects, refer to the CEWindowsAPI class reference.