The following procedure defines the steps involved to build a basic screen using Visual Basic 6.0.  The tpriNtRt administrator program is used to begin a new Visual Basic screen.  All the user has to do is add controls and design the layout of the page.  Below is a screenshot of the Visual Basic design interface and descriptions of the layout:

1. Run tpriNtRt administrator program D:\locNtRt\tpriNtRt\Apps\tpriNtRtAdmin\tpriNtRtAdmin.exe

2. Enter screen name, e.g. ‘l3Main’ with appropriate mill site prefix, in this case ‘l’ for Location

3. Click ‘Generate New Screen’

4. A list of steps for creating the demo screen is displayed; those items that are checked have been automatically finished, those that are unchecked must be performed manually

A Label object will always be used for the non-changeable background text on a screen.

1. On the toolbox to the left, choose the label control.

   

2. Position the mouse where the object should be placed on the screen, hold down the left mouse button and drag to the desired size.

3. Naming the object is optional, but should start with lbl.

4. Set properties for label such as font, fore color, and back color.

For adding additional objects to the screen such as TelePro controls, refer to Section 6.5 [LINK] of this document

1. Select the Menu option File, Save Project

2. Select the Menu option File, Save uc[name].ctl

1. Remember to close all instances of Internet Explorer when making your page.  If not, the page will not be updated correctly. 

2. Select the menu option Run, Start With Full Compile (or Ctrl+F5). This ensures that all code is tested and all variables are defined. 

Pages can be quickly rebuilt and/or published using a program called tpriPublisher.

D:\locNtRt\apps\tpriPublisher\tpriPublisher.exe, this program allows the user to select multiple screens and can rebuild, publish, or both with a single mouse click.

• Save often:
  Every time you make a change that you wouldn’t want to do again, SAVE your project.  Ctrl+S, click disk button, or File, Save all work.
  

• Auto-Complete:
  In the editor, on-the-fly syntax and programming assistance will give you a pull down list for completing what you started typing. You can just press tab to write out what is highlighted.
  

• Fine Movements:
  Instead of moving objects on the screen with your mouse (which lacks precision), you can use the ctrl + arrow keys to move the object in fine increments.
  

• Lock Controls:
  Once you have finished designing the page, you should lock the controls in place so that they are not accidentally moved (there is no way to undo a move).  This feature can be toggled on and off from the Format menu.  Even if Lock Controls is enabled, you can still move them using the ctrl + arrow keys.
  

• Aligning objects:
  To make the objects on your screen align horizontally or vertically, select the objects (either by dragging a selection box with your mouse over them or by individually clicking on each object while holding down the ctrl key) and in the Properties window, set the Top or Left to a number.  This will change the properties for every object you have selected.
  

• When editing the code, I move the arrow keys, but nothing happens: 
  Sometimes when you are working in the code view, the focus will still be on an object in the object view.  Every time you press an arrow key or page up/down, the focus is actually changing on the object view.  The fastest way to stop this is to close the object view.
  

• Tab Order: 
  It is a good idea to think about the tab order of all of the objects on the screen.  If the user tabs to a non-data input object, it is possible that s/he may not see the focus outline and think the screen has frozen.  Suggestion: allow tabbing only to data entry boxes and command buttons.
  

• Toggle between object and code view:
  Ctrl + tab switches the window, but both must be open first in order to toggle between them.
  

• Debugging the code: 
  There are many helpful tools used for debugging the code. You may set a breakpoint with the F9 key (the breakpoint stops the code before that line is executed), step through the code with the F8 key, and run the code again with the F5 key.  Once the code is at a break point, you can view variable values by hovering over them with the mouse or entering the Immediate Window and typing “?” followed by your variable and press enter (example:  ?myString).  You may also add a watch on any variable you choose. This is a quick way to view many values at any breakpoint.
  

• ‘Conflicting names were found…’ error received when opening a VB project:
  This error is cause when the user-control (*.ctl file) was originally saved in lower case and then later saved using upper case letters. In this case, VB is case-sensitive, but it does not update the code inside the .ctl file. You have to manually change the code in the .ctl file to get rid of the error.   Just open the .ctl file in your favorite text editor and do a search for “Attribute VB_Name =”. This will bring you to the line in the code that needs to be changed.   Just edit the file name that is in quotes to the correct case and you are done.

The following is an overview of the VB error handling logic for ActiveX screen code.  Including the following in your screen code will provide an orderly handling of VB errors if they should occur. 

In the case of an unplanned VB error the program will present a Windows message box reporting the error condition.  Then the program will shut down and close the browser.

Several standard lines of code are required for each screen.  The IobjSafe.bas module is automatically included in your project.  The ErrRpt Subroutine called by the error handler is included in this code.  The following is automatically included at the start of your code.

Option Explicit
Event GoToURL(Url As String)
Event ErrorTerminate()
Implements IObjectSafety

The following sample shows the base framework for a Sub or Function

Private Sub DemoSub() As Long)
Dim liTmp AS Integer

 

 On Error GoTo ErrorHandler             <- Set the location to branch to in case of error
 mbError = False                        <- Reset the error flag variable

‘ Start of your Code
‘ blah blah blah         
‘ End of your code

On Error GoTo 0                             

Turn off the error handler for this sub.  This is important.  If you omit this line it is possible that an error generated in some other section of the code will branch here and report the wrong failing program location.

Exit Sub                            

Exit   (Note: If you have written a Function then change to Exit Function)

ErrorHandler:                             

The following is the general error handler. Based on the error number, the program will proceed.  If your code may generate an error that is expected under normal operating conditions, then handle it here.  If the error is not included in the list of Select statement Case numbers, then the code will call a general purpose reporting procedure.

Select Case Err.Number

Case 9                                   

For example if error number 9 (Subscript out of range) is generated by a bad user data entry, then you may catch it here and respond.

MsgBox "The value you entered is not valid!  Please check your input"

                        mbError  = False

Case Else

ErrMsg ("DemoSub")      

Update this text to indicate the Sub or Function name.  The string will be included in the error message reporting.

You may also add any additional debug information.

End Select

   If mbError Then                                      

If mbError is true then the ActiveX code will call back to the browser via the ErrorTerminate event.       

RaiseEvent ErrorTerminate
 Else
      Resume Next

If you handled the error and would like to have the program continue, then set mbError to False.

End If

End Sub

Following are the run-time errors defined by Visual Basic:

The following sequence is used to add property pages to an ActiveX Control.  This sequence was used to add property pages to the TelePro supplied controls.  It is included here for documentation purposes only.

1. After loading your ActiveX Control in Microsoft Basic you click on Project —> Add Property Page.

2. Click on the icon of VB Property Page Wizard and on Open button. New window appears: “Property Page Wizard – select The Property Pages”. Two Property Pages are created automatically: StandardFont and StandardColor.

3. If you want to add a new one then you should click on the button “Add” and the new page name. Repeat this step as many times as you need. You also can change the order of pages using arrows at the left part of the window.

4. After all you click on the button “Next>”. In this window you can choose which properties will be in your pages (color and font properties are added to “StandardColor” and “StandardFont” automatically).

5. When all properties have been assigned to the pages click on “Next>” and finally on “Finish”.

Use the following prefixes to indicate a variable's data type.

Some Examples:

Dim dbBiblio As Database
Dim recPubsInNY As Recordset, strSQLStmt As String
Const DB_READONLY = 4                                               ' Set constant.
'Open database.
Set dbBiblio = OpenDatabase("BIBLIO.MDB")
' Set text for the SQL statement.
strSQLStmt = "SELECT * FROM Publishers WHERE _
          State = 'NY'"
' Create the new Recordset object.
Set recPubsInNY = db.OpenRecordset(strSQLStmt, _
          dbReadOnly)