If you used other visual development environments, then you most probably have already mastered the art of design. (A topic that we will not do anyway.) We do not concentrate on the code in this chapter either. This chapter is to get you comfortable with the programming environment that PeopleSoft provides. If you already program in some other language, then you may not be too happy with everything PeopleSoft does. C programmers among others will be the ones who get most upset as PeopleSoft puts all programmers on one same level. There is no way except through comments to figure out who wrote a piece of code. Try as hard as you might to format the code and PeopleSoft reformats it to a standard setting in the end.

This is just one of the few things about PeopleSoft that you will hate or love. There are others. Programmers at PeopleSoft tried as far as possible not to reinvent the wheel. If there was something else that could do it better, then that something else was used. For example, COBOL is a language of choice when it comes to defining the business rules to be followed. The language has been refined so much that there is little value that PeopleSoft could add to it. Further, rewriting COBOL commands in PeopleCode would simply be a waste of time. So PeopleSoft left it alone. PeopleSoft only looks at managing tables and data through panels. There is nothing more than the panel to get any work done in PeopleSoft. Every command that you require is available. If one needs additional functionality that PeopleSoft missed out, then the facility to call in routines written in other languages like C is always there.

This chapter, as with most chapters in this book, takes a different approach. The focus is still the same — to teach you how to write great applications using PeopleSoft. And to do this, you will never be swamped with a long program that has lines of code to understand in one go. Rather you will always have small examples that you can try out, test and then put together to get the final result.

Another peculiar aspect of this chapter is that none of the examples really do anything ‘sensible’. You will find that the names used for objects — fields, records, panels, never make any sense. At least, they do not appear to. Remember our purpose here is to teach you to program and not to write 'pretty' code. Tying in long field names, record names, etc., may make sense when writing a full-blown application. But while learning and when you desperately want to see results, writing in long names only wastes time. We could keep discussing the merits and demerits of this as they say "till the cows come home". (If we were in North India, in a state called Bihar, we'd stop just now, for the cows are home… and in the Chief Minister's house too.) However, it would serve little purpose. So let's get on to our work. We believe that your confidence will grow and your concepts will be clearer if you take this program byte-by-byte (well, not really that slow.)

Before starting on this chapter, you need to be familiar with the Application Designer. This is the tool that does everything. It is assumed that you know how to develop a simple application, i.e. to create fields, records, panels, panels groups and menus. It is also assumed that you are of average intelligence and that you can add 2+2 and get a result of 4. If not, you could enroll for a course in speed mathematics that will be showing on site near you soon! If you do not have any of the previous skills, DO not go on. Attempting to read more than the next couple of lines of text will cause the green genie who sits in your monitor to breathe fire and destroy your computer. The only concession that can be made is if you can add 1+3 and get a result of 4. You can? Good. Go on.

Tradition has it that the first program that anyone writes in C is "Hello World". It has something to do with the words that Neil Armstrong said when he landed on the moon. He looked down at that mass of blue-green, and said — Hello world, I'll be back some day. And I'm gonna be a star. Since C was the language used for programming the rocket that sent him to the moon, all C programmers are now taught to write Hello World in their first C program. Of course, if you did a C course with us, you would start with something different, as if you believed all of the preceding stuff, you'd believe anything. Still, just to keep with a new tradition do remember to key in a quick, "Hello PeopleSoft" when you try out your first program. We will show you how to do it.

Quickly revise all that you learned so far. PeopleSoft changes the way one works with databases by changing some of the basic concepts of RDBMS'. Fields are the most basic components of a database now. These have to be defined first. These fields however cannot be used directly, and must be inserted as part of a table, which PeopleSoft calls a record. This record is not to be confused with a row or a set of data that is entered into a table. Only record fields can be used for storing data. Again, in PeopleSoft, this can only be done through a panel. Panels are everything in PeopleSoft. One can use a panel to Add, Update, Display or even correct the data in the table. Building panels is not difficult at all. It is just a question of placing fields on the panel and then selecting the Action to be associated with the panel. There are only five Actions or tasks that can be performed on a panel — Add, Update/Display, Update/Display All, Correction and Data Entry.

Panels can be used only through menu items, which are linked to panel groups. It is also possible to modify existing panels and change the code associated with them. By copying and moving defined record fields from one panel to another, one can also copy the code that is associated with the field. Program code cannot remain in isolation. It needs to be attached to a field and written in some event of the field. Hence one of the first things to do, is to create a panel with fields to be for writing the code.

To ensure that you do not go off alone, try to replicate the same field names and other objects as we do here. Do this so that there is no confusion with what-you-see-and-what-we-get (WYSAWWG, pronounced what-you-see-and-what-we-get). You will find that acronyms like these keep popping up in the computer industry and hence do not get fazed by them. We will add in our fair share and show you how to do the same for free. If by the time you end this book, you cannot talk double-Dutch or your boss still understands you, then we have failed in our duty.

Create a two fields — FF1 and FF2. Both fields should be of Character type and length 10. Label them FIELD1, FIELD2 and FLD1, FLD2 for the long and short names respectively.

Next create a record to place the fields in. Call the record RREC1 and make FF1 the Search key. The record fields now have to be placed on a panel, hence create a panel and name it PPA1. Having done so place the fields on the panel. Now create a panel group to go along with the panel.

Name the panel group PPG1 and include panel PPA1 in it. Since there is no other table or panel to be included, save the group. Set RREC1 as the Search record. Also select all the Actions — Add, Update/Display, Update/Display All, Correction and Data Entry — for the panel group.

The last thing to do is to create the menu and to link the panel group to this menu. Save the menu as MMENU, and label the main menu item MMNU1. Under this, place a sub-menu item called LABEL1. Do not forget to link the panel group PPG1 to this sub-menu item.

It would be a good idea to save the entire project as the panels and fields will be used over and over again. Call it PPRJ. Test that all this works before going on. Try adding, updating and correcting data in the table. If you do get an error when trying to do so, it would be because you forgot to build the table before using it. Do this and re-run the program.

Test completed? Run PeopleSoft. Click Go | PeopleTools | Application Designer. Open project PPRJ and then display the only panel in it — PPA1. You are no ready to enter your first line of code. To do this, right click on FIELD2 as shown in fig.1 to open the pop-up menu.

Of course, this is a silly menu item. There is no PeopleCode in the field at all. Edit PeopleCode would have been a more descriptive entry, as it could be used for code that will be placed as well as code that is already placed. But then, with so many things already on the PeopleSoft programmer's mind, this hardly seems like a major issue. Some of the other software companies have got away with worse — to a point where customers even paid good money to get conned. If this really bothers you, you can open the XXXX file in a hex editor and change the bytes View to Edit. Do remember by doing this, you will have violated your license agreement and you will no longer have any right to the paid support service that is freely available.

Selecting View PeopleCode will cause the display to change. It should look like fig.2. If the window of the right is not an exact fit, maximise it.

While you are already know what a field is, and that when referring to fields on a panel it actually means a record field, an event in computer terms may not be clear. We did tell you at the beginning, that computer people love complicating life. Although everything is simple, there is need to add a bit of mystique. An event is not really something to worry about. It is a happening. Something like your birthday. Like it or not, it occurs every year. (Some women would die just to stop from ageing, literally. After all, when you are dead you age no more. You just get mouldy and rot in some grave. C programmers live on forever!) Another daily event could be breakfast, or the fact that you get up or go to sleep. It could be the first time you and your friend held hands, kissed, made out, that sinking feeling as you went to the altar with a shot gun behind your back, because of the previous event — anything at all. Events could be just anything. On the computer too, 'events' are continuously taking place. However, PeopleSoft has selected or predefined few which can be used to place code in. Click on the down arrow of the list box and you will see what events are available.

Events determine what happens next in a program. Code is written in the events, and is executed each time the event occurs, is triggered or gets called. This is automatic. For example, a smoker automatically reaches for a cigarette as soon as he gets up. Or if you are a normal human being, the inferiority complexes as you find you know less than us.

The list of events recognised by PeopleSoft is rather short but can definitely be used to cover all situations in PeopleSoft. Being predefined by PeopleSoft, the list cannot be changed or added to. At least, not by you. As to why the list is so short or what else can be added to this list is not really our concern. This is the PeopleSoft collection and should be accepted as such.

Fortunately, the events listed in the event drop down box are not cryptic. All of them are simple English words. Since the event can only be a single word, upper and lower case is mixed so that the words make sense. The initial letter of a word is capitalised. For instance, the FieldChange event is displayed with the F and C capitalised. This event is always displayed when the View PeopleCode window is opened. 

Select the FieldDefault event as this is the first event in which we will write code. Even a single semi-colon is considered code by PeopleSoft. The semi-colon like many other commands that you will see in PeopleSoft appear to be borrowed from C. C programmers will be quick to identify the semi-colon as a full-stop or a sentence terminator. Code does not have to be formatted in any particular order. The semi-colon will let PeopleSoft know when the line is completed. (You will see that whatever you do, your code will be reformatted by PeopleSoft before it is stored.) It is silly, but with each new language that appears, there are new rules to be learned. In fact, there should be some body that defines and standardises the syntax that can be used with a language. The semi-colon is particularly silly as PeopleSoft relies a good bit on COBOL and COBOL uses full-stops to delimit and define the line ending. Hence, adding another line terminator does not make any sense. The COBOL programmers use a full-stop, This semi-colon that you write does not generate any error as there This event is ‘occurs’ before the field is displayed on the panel. It could be used to initialise the field or perform other tasks that are to be completed before the field is displayed.

Since the event entry was not bold, it does not contain any code. The code window will be blank. Enter the single line of code that you can see in fig.5. This line

ff2="hello" ;

Initialises the field FF2.

FF2 = "hello";

No matter how hard you try or how badly you format the code, it will always return to this. Variables and field names get capitalised. Spaces are inserted before and after the equals sign, and any space before a semi-colon is removed. Later, keywords and functions, when used will also fall in step with PeopleSoft.

The other change that takes place is that the event label becomes bold. This can be seen by dropping down the event list box.

Now that you saved your application, you can test it by restarting PeopleTools. If you already tested out the application before this, then the application will already be placed on the Go menu. Click Go | Mmenu and start the application. 

There will be only one new menu option on the main menu bar — MMNU. From here, select LABEL1 and Add to make a new entry. A prompt for the Search record will appear, as seen in fig.8. Since the Search key was set to FIELD1, enter a value and proceed. If you get an error at this point, it would be because you did not create the table after defining the record. Go back to the Application Designer, open the project once more. Click on Build | Project, select Create Tables under Build Options and Execute and build script under Build Execute Options.

FIELD2 is a different story. If you figured that this value has something to do with the code that was entered in the event FieldDefault, you figured right. However, if you check the lines of code that you entered, you will find that the hello entered was lowercase, while the one that is displayed is uppercase. This is because when the field was created, the Format defined was Uppercase. The properties for a field are carried down to the records which they create.

Save this value so that there is some data in the table. Return to the Application Designer to try other functions.

Back in the Application Designer, select the field FF2 and the event FieldChange once more. Replace the code that is present there with

winmessage ( "FieldDefault",64 ) ;

ff2="hello" ;

Once more, the autoformat will take over and reformat the lines of code when you save the project. Space the keywords and the rest out and you will still find that it all comes together once more, as in fig.11.

Close the project and then run the application once more. Again, select Add under the menu LABEL1. Enter 2 at the Search record prompt and click OK. 

The value 64 placed with the WinMessage function displays the information icon. There are other values that you can try out while using WinMessage. More details about this function can be found in Help.

Value Meaning

0 One push button: OK.

1 Two push buttons: OK and Cancel.

2 Three pushbuttons: Abort, Retry, and Ignore.

3 Three pushbuttons: Yes, No, and Cancel.

4 Two push buttons: Yes and No.

5 Two push buttons: Retry and Cancel.

0 No icon

16 Stop-sign icon.

32 Question-mark icon.

48 Exclamation-point icon.

64 Lowercase letter "i" in a circle icon.

0 First button is the default.

256 Second button is the default.

512 Third button is the default.

(To combine the different buttons with icons and button defaults, add up the values.)

Save this record too. Now there will be two records in the table. Restart the Application Designer, and open the project once more. Now try the following line of code.

^="hello"; 

Simplification is the name of the game. In actual practice, when referring to any field, one precedes the field name with the table name. The two are separated by a period (.) like RREC1.FF2. Try doing this in the current record and the table name is dropped. For example, try

rrec1.ff2="hello" ;

This will reformat to

FF2 = "hello";

In a way PeopleCode has been optimised as far as the formatting and readability of the program is concerned. All this makes PeopleCode much easier to understand, while leaving a programmer no way in which to leave his own personal mark.

It’s time to move on again. Do not waste time trying to figure out why FieldChange is the default event in the event list although FieldDefault is called first when a panel is displayed. The answer is simple and silly. List boxes here are always arranged alphabetically, hence since C comes before D, FieldChange is on the top of the list. If there were more events, then possibly something else may have been displayed.

FieldChange is displayed only when there is no code in any of the other events. As soon as code is placed in any of the events, the last event edited is the one that is listed in the event list. Do not delete the code in FieldDefault but move to FieldChange as in fig.19.

FF2 = "BYE";

But before you do, pause for just about a minute to try and figure out what the FieldChange event will do and when exactly it will appear. Will it appear when the contents of the field are changed? Or will it appear when you change from field to field? Does it appear before or after a change has been made?

To move the highlight or cursor from FIELD1 to FIELD2, use the mouse or press Tab. Moving into the field does not call the event FieldChange, but click on FIELD1 once more and you will see fig.23.

The easiest way to check when each event gets called is to place a WinMessage in each of them and observe when the event gets triggered. Delete any of the old lines of code as they will not be required anymore. Do all the events in one go. There are not many events as you can see in fig.24. Save the project and run the application again. As usual, Add in another record.

WinMessage("FieldEdit 16", 16);

This will have the Stop sign appear with the message box when the FieldEdit event is triggered. The purpose of putting in all these lines of code is to learn the sequence of events being triggered. You already know that the first event to be called before anything appears on the panel is the FieldDefault event.

After this event is triggered, the FieldFormula event is the next one called as seen in fig.27.

Look at the bottom left of the screen. The message that appears there states what is happening at any given time internally. At this point, the panel is still being loaded or created on the screen. The fields will only appear after another two events get fired — FieldDefault and RowInit, which is seen in fig.29.

To continue with the event run, enter HELL in FIELD2. It would be silly if every time one entered a keystroke in a field an event got fired. Hence, it is only once all changes to a field are made and the cursor has left the field, that PeopleSoft recognises that the contents of the field have been modified. Press Tab and the FieldEdit event is triggered. It is triggered just before the FieldChange as the change in contents is recognised first.

Pay attention to the bottom right of the panel once more. You will find that the Field Change is another ‘service’ that is processed. The FieldFormula event is called again, and this is not the last time that it will be called. It will appear again and again. However, at this point of time, all we are concerned with is getting the sequence of event right. Do not try to figure out too much about the ‘Why?’ just now. It will become clearer as we go along.

At this point, everything comes to a standstill once more, so to keep going on, click on Save and fig.35 will appear on your screen.

FIELD2 will correctly display HELL, as this is the value that was stored along with FIELD1 as 4. With the panel now correctly displayed, everything now comes to a halt. The users needs to perform some action before any other trigger is fired.

To force an event, delete an L of HELL and leave the field. By doing so, at least two events should be called — FieldEdit and FieldChange. And they do. FieldEdit gets called since the contents of the field were modified. FieldChange is called each time the cursor moves out of a field. FieldFormula gets fired again and once more there is a pause.

To push things on again, Click Save to record the changes made to the fields, and the following events are triggered — SaveEdit, SavePreChg, Workflow and SavePostChg. That there should be a SaveEdit and another three events before the record is committed, seems strange. However, all these events are useful and are made use of by PeopleSoft in its own code/programs. As you work through the examples that follow, the use of each event will be clearer.

There is no difference between Update/Display and the Update/Display All Action. The events that both trigger are exactly the same. Use the same record as in the last example by entering 4 in the Search record field. This will call the events FieldFormula and RowInit. The record will be displayed before RowSelect is called. It is now possible to edit the fields, and this time change HEL to HELLO.

Since a change in the field contents has been made, FieldEdit will be triggered. FieldChange follows this as you move out of FIELD2. This is followed by FieldFormula and the display pauses for user input. Again, save the entry and another set of events will be fired. These are SaveEdit, SavePreChg, Workflow and SavePostChg.

Do this one last time for the Correction Action. Once more use Search record 4 and observe the events that get called. FieldFormula and RowInit start the ball rolling and are displayed before the field on the panel are displayed. After this, RowSelect is called and one can edit the fields. Change HELLO to BYE and leave FIELD2. FieldEdit and FieldChange get fired. Save the entry and the last sequence of events get triggered — SaveEdit, SavePreChg, Workflow and SavePostChg.

Though there are different names to each Action, the sequence which the last three Actions follow, are exactly the same. Add is the only Action that is different. Therefore, Update/Display, Update/Display All and Correction could be used interchangeably. One can enter code in the field events to control input.

Since you now know when the events appear, it is time to move on to a bit more code. A field can be filled with data either though the keyboard or by an assignment statement. Defining a default value for a field could be done in any of the events, as it is possible to use code in one field to assign a value to another. It is also possible to assign values to fields through variables. This is helpful when one has to create a value that is a sum of parts. In this case therefore, the resultant value is created on-the-fly.

Verify the field-variable assignment by first deleting the code in all events. Now in the FieldChange event, key in the following

&A = "good";

FF2 = &A;

You know by now, that you do not have to worry about the formatting. PeopleSoft will take care of this for you as soon as you click Save, as you can see in fig.43.

If you look back at all that you have done so far, you will realise that there must have been some code that was executed when you replicated the PeopleSoft panels. There was. The code was not noticed because at no point did we ask you to open the View PeopleCode menu item. Where then is the code hidden? With the record fields.

In the last few examples, code was entered under the events that were available for record fields placed on panels. This is visually represented in the project tree as well. Expand every branch of the Records folder and you will find the field FF2 has an entry under it — FieldChange. The lightening bolt icon is possibly the programmers way of saying something electrifying happens in the field. Check this out in fig.45.

Try copying a field or a record. If there is code in the record, a prompt appears to confirm that the code is also to be copied. For example, select record RREC1. Click File | Save As and enter RREC2 in the dialog box that appears. Fig.50 should appear on your screen.

Do another Save As. This time name the record RREC3 and click No when prompted to copy the code. The display will change once more and you will find that the Yes has disappeared from the FCh column.

What makes things even worse is the rich set of tools that are available and the ability to call in even more using links with other languages. A programmer could well get swamped. However, if one really breaks an application into its separate parts as PeopleSoft did in defining fields as the basic unit, programming PeopleSoft is much easier and definitely fun. This we will prove in the coming chapter.

In this chapter you have learned about a few of the PeopleCode commands. WinMessage is the easiest to use when debugging and testing. The code can only be attached to fields under special links called events. These events get called or are fired depending upon the users or the program actions. Since the code is attached to the record field, copying or using the field in another panel or application also copies or allows the code to be used in the other application. This can be prevented if the user wishes to do so.