PD Lookups/Drops Bundle - ProDomus

Posted March 1 1998

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It has been said that the devil is in the details, but I have often found that the money is in the details as well. Many times, it's the small things that push the sale of an application over the top - the little enhancements that make the user go "Wow! This is slick!" or "Hey, this works just like..." and they name a major commercial application. I call this the 'Wow' factor, and fortunately for all of us there are a number of Clarion third party add-ins which make it easy to add it to our own applications.

One product that falls into this category is the ProDomus PD Lookups/Drops Bundle, which actually contains two individual but complimentary products - PD Lookups and PD Drops.

What do they do? In a nutshell, they help ensure that your users enter valid information into the fields on your Forms. They are designed to be used anywhere that a user entry can be validated against a file of approved items, and they are used in place of the standard Clarion methods for doing that: the Field Lookup Button template, the File Drop List control and File DropCombo control.

What's the difference between the two? At the most basic level, it is in the approach taken to presenting the list of valid choices to the user. PD Lookups uses a separate Browse procedure for the user to select an item from, while PD Drops remains on the Form and uses variations of a drop-down list.

Major Features

Let's take a look at what each of these templates does.

PD Lookups

Lookups offers the following enhancements to the standard Clarion method of validating an entry value against a file:

• The library fills in fields with the closest matching record as you type. This is the feature with the highest 'Wow' factor.
• The lookup browse can be popped up via any of the following methods: A double mouse click anywhere inside the field, clicking a look up button, or pressing Alt-Down arrow (holding down the Alt key while pressing the Down arrow key).
• You can scroll through the validation file while editing the entry field using the Up and Down arrows.
• The lookup button can be either hidden or disabled until the lookup field is selected.
• The lookup button is automatically skipped when moving to the next field, avoiding an unnecessary extra Tab key press between fields.
• You can do multiple lookups into another file on the same Form without having to alias the File.
• You can lookup one value, yet save another. For example, the user can enter and lookup a company name, but you save the company ID number in the file.
• Supports the display of hot fields while you are entering data into a field. An example of this might be where, as you enter a state abbreviation, the state name is displayed in a string field next to it. Scrolling up and down through the field with the arrow keys would automatically display the state name as well.
• Overall Lookup behavior options can be set globally, allowing the user to customize how the lookups work. Options that can be set include whether or not the lookup browses should automatically pop up on the first invalid entry, whether a sound should be played and if so, which sound, and finally, whether the lookup button for a non-selected field should be visible, disabled or hidden.

PD Drops

PD Drops consists of two templates - a File Drop and a File Drop Combo. They have the following features in common:

• The list of valid values can be dropped down either by clicking the drop button, or by pressing Alt-Down arrow.
• You can scroll through the validation file without dropping down the list, by pressing the Up and Down arrows.
• Both templates can scroll and display one value while saving another into the data file. A prime example would be where the user selects a company by name while the program saves the company's unique ID number into the file.
• Both templates allow multiple lookups into the same file without aliasing.

Additionally, the PD DropCombo template has the following advantages over the standard Clarion DropCombo:

• The library fills in fields with the closest matching record as you type. Once again, this is the feature with the highest 'Wow' factor. The documentation also states that the library uses a binary search to quickly fill in the entry.
• You can make the lookup optional so that values that are NOT on the list will be accepted. Additionally, you have the option to allow blank entries.
• You can use either hot keys or a right click menu to pop up a data entry form to add new items to the list.
• You can use optional sorting to turn off CW's case sensitive sorts.

A further major improvement over the standard Clarion templates that both the Lookup and Drops products have is the ability to use filters and ranges on the files in which you are looking up data. This allows you, for example, to combine many types of codes in a single file while restricting the various lists to only the codes valid for the field you are currently on, or to limit company lookups to only active companies.

Installation

Since the products can be purchased separately, they each have their own individual installation packages. Installation for both products was virtually identical - unzip the install package, run the enclosed SETUP.EXE, and then tell it where Clarion is installed (it defaults to C:\CW20 or C:\Clarion4 depending on the version). Both the product and a demonstration application are then installed and you are done. Simple and straightforward.

A few improvements could be made, though. First, it would be nice if the installation program let you select the program group in which it will install its program items. For example, I have a LOT of programs installed on my machine so, to keep my main Win95 Programs menu from spilling off the screen, I prefer to place Clarion add-on items inside the Clarion For Windows program group rather than have them at the top level.

Second, it would be helpful to have the install program automatically display the ReadMe file to ensure that the user sees the contents of that file. In the same vein, the ReadMe file should have an entry in the Program Group the installation creates so the user doesn't have to go searching for it.

In any case, after the usual mandatory registration of the templates in the Clarion IDE, you are ready to begin using them.

Implementation

To use either (or both) of these products in your application, you must first add a global extension template which, in essence, tells your application about the PD Lookups and/or Drops libraries and functions. A separate global extension template is added for each desired function; Lookups, Drop Lists and Drop Combos. For each, you can specify whether their respective libraries are linked directly into your program or used as DLL's.

For PD Lookups, you next add a code template to your application's Main procedure, usually in the 'Procedure Setup' embed. This template is where you specify the default behavior for lookups, such as whether to hide or show the lookup buttons, if sounds should be played, if the lookup should pop up automatically as soon as an invalid entry is typed, and a few other options.

To use the Lookups or Drops templates themselves, you go the Form with the fields you want to validate and populate the appropriate control template. The examples below show some of the options for the Lookups and DropCombo controls.

Action properties for a PD Lookups button

Action properties for a PD DropCombo control

While the wealth of options might seem intimidating at first, you'll find that you quickly grow to appreciate the flexibility they provide.

Probably the biggest decision you face when implementing these products, though, is which one to use in a given situation. Each approach has its strengths and weaknesses, so let's take a quick look at them.

The 'big' factor - how many records?

The primary deciding factor is the size of the file, or if using filters, the size of filtered record set. PD Drops, like the standard Clarion File and DropCombo drops they replace, are 'file loaded'. What this means is that the entire file or record set has to be loaded into memory before the drop can be used, so drops should only be used in situations where there is a relatively small number of records. TopSpeed recommends a maximum of 100 records. Lookups, on the other hand, use a 'page-loaded' Browse, which means that it only reads as many records as it needs to display. So, if you are validating against a large file (looking up a Part Number, for example), a Lookup is really the only way to go.

Lookups

Like the standard Clarion 'FieldLookUp Button' template, it is designed to replace, PD Lookups is implemented as a Control template which places a lookup button on your Form or Window. Unlike the standard '...' button, the Lookups button has an underlined down arrow on it (the icon is provided with PD Lookups).

One of the advantages of using a Lookup is that it does use a separate Browse procedure to display the list of choices. This means you have access to all of the normal formatting, multiple sorts, hot field display and so forth which a Browse provides. I find this option best for situations where there is a lot of secondary information which can help the users make their choice, or when they would want to be able to search in different ways. An example might be looking up a Company name or number. Having a browse would enable them to see additional information such as the location of the company, contact information or any other pertinent information you would wish to display.

Drop List

Drop Lists can be less intrusive to the users' flow during data entry, since their attention remains focused on the Form itself. Since Drop Lists do not allow blank or invalid entries, they are best used in situations where information is required, and you do not want to allow any updates of the list during data entry. Since a single field is usually displayed, this type is ideal for use with codes, etc. An example might be a list of priority codes, such as Low, Medium, High and Emergency. The user types 'H', the field is filled in and they are done. If there are multiple codes beginning with the same letters, they only need to type enough to distinguish the one they want. Behind the scenes, your program will only store the unique internal value for the code (an ID number or single letter, for example).

DropCombo

DropCombos are also less intrusive to the users' flow during data entry, since their attention remains focused on the Form itself. You have more flexibility in allowing entries, plus you can use an update Form to capture new values. They are still best used in situations where there is not a lot of information you need to display for users to make their choices, since multiple columns quickly make the drop down list rather wide and unwieldy.

Performance

Having used PD Lookups for a long time, I have seen that applications containing this product invariably elicit favorable comments from my users. This style of 'intelligent' data entry was popularized in hugely successful commercial applications such as Intuit's Quicken financial package.

How does it work? For example, if you had a list of states and typed a 'C' into the state field on a Form, it would automatically fill in California. If you continued typing and pressed 'O', it would switch to Colorado. Press 'N' and now you have 'Connecticut'. As soon as the field is filled with the correct value, press Tab and you are off to the next field (unlike the standard CW lookups where you have to Tab past the lookup button as well). Meanwhile, in the background, your application is storing the abbreviation for the state, or a unique ID number.

It should be noted that, because it is not actually a data entry field, the PD Drops File Drop doesn't have the exactly the same look-ahead data capability as the other templates. It does, however, have a slick combination of an incremental and entry locator, automatically selecting (and filling in) the entry as you type. From the user's point of view, it would be hard to tell the difference.

In any case, since this kind of behavior is much better seen than described, I recommend that you download the demos of these products and experience them yourself. (Information on obtaining demos is provided at the end of the review.)

Documentation

Documentation is provided in the form of a Windows Help file for each product. A 'ReadMe' text file details the most current changes and features, and is automatically installed in the product directory.

Overall, the help files are detailed, but rather difficult to read. Though they contain reasonably good instructions and a few scenarios for use, it almost seems they make the process more complicated than it really is. Finally, they both contain spelling errors that need correcting, with the Drops help being the worse of the two.

Fortunately, the demo applications which are included with the products are really well done, with loads of onscreen help describing which features are being used, and how. So, between the demo applications and the help, you shouldn't have any real difficulty in putting the products to use. Further, once you have actually done it a few times, you'll find it is actually very easy to use.

No printable documentation is provided.

Technical Support

Tech support is excellent, with email questions answered accurately and in a timely manner. Suggestions for improvements are often quickly incorporated into the products, and ProDomus seems committed to enhancing and extending the templates as new needs arise.

Support can be obtained either via email or on the TopSpeed CompuServe Third Party Vendor forum. Fax and phone numbers are also provided in the documentation, but I never felt the need to try them out.

ProDomus also maintains a web site where information and the latest versions are always available for download (passwords are required to unzip the downloads). A nice touch is that they always specify the date of the last update for each product, making it easy to see if there is a newer version available. Additionally, registered users are notified via email anytime ProDomus releases an update.

CW 2.x and C4 Compatibility

Versions of the bundle are available for CW 2.x and for C4. The C4 version includes templates for both the Clarion (CW20) and ABC template chains. Functionally, they all work the same as far as I can tell, though they occasionally leapfrog over each other as new features are added to one before the other.

Summary

Can stock Clarion perform the types of data validation that these products provide? Basically, yes - but with nowhere near the flair and flexibility of the Drops and Lookups templates. Once you have used the templates a few times, you'll find them both easy and fast to implement, and your users will thank you for the way they make their jobs easier as well.

How? Because while developers tend to think in codes, abbreviations and ID numbers which are efficient to store, users think in terms of names, terms and descriptions that have meaning in the 'real' world. Products like these enable you to easily satisfy both requirements - users get to enter and lookup familiar terms while your program maximizes its efficiency by storing the smallest possible unique values in your data files.

To summarize, if you want to add a good dose of the 'Wow' factor to your applications, I strongly suggest you check these templates out!

* Source for the look-ahead data entry function is not available. You can however, disable those functions in the global extensions, in which case only standard template code is generated.

The ProDomus Lookups Bundle lists for $89 US for either the CW 2.x or C4 packages. Individually, PD Lookups and PD Drops are available for $49 US each. Upgrade pricing is available for registered users. The templates can be obtained either directly from ProDomus (860-233-0705, VISA and MasterCard accepted) or via CompuServe Software Registration service (SWREG).

PD Drops and Lookups can also be purchased through the TopSpeed Accessories program in a bundle which adds the PD Date Tools (a nice pop-up calendar and other functions for manipulating dates, etc.). That bundle lists for $149 US. TopSpeed sales can be reached at 800-354-5444.

For more information on pricing or to download demos of these products, visit the ProDomus web site at: http://www.tiac.net/users/prodomus. The demos can also be downloaded from the TopSpeed CompuServe forum, Third Party Vendors section.

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