Re: Announcement: Multivalue on a PDA



Tony Gravagno wrote:
It's very neat stuff and all, but I hope developers don't get too
confused here: "easy for the vendor" should not translate into
"desirable by the consumer". Your blue-screen character app in
Windows XP may get the same luke-warm reception as your blue-screen
character app in Windows CE. If you have a real business case for
deploying a PDA solution, consider your audience carefully, understand
what they expect from these devices, and don't go too far down the
development path before asking a test audience how they feel about the
new offering.

I'll ask one simple question: if you port your MV app directly into a
PDA, do you really expect people are going to use a stylus/pen to
enter data the same way they would if they were typing? No, you're
going to have to whittle down your MV app so that it both fits on the
small screen and so that it eliminates as much data entry as possible.
You're also going to need to do a lot of testing find a balance
between having a helpful amount of data on-board and keeping your
sorts small. Other considerations will become apparent as we get more
familiar with the nuances of this new option.

Before I wrote my first PDA application, I bought a book "The Definitive Guide to the .NET Compact Framework" by Larry Roof and Dan Fergus (Apress). It's a little dated now (based on CF1.0), but still has very useful information.

One chapter was "Designing an Effective Interface" and it had some common sense rules that only an experienced PDA developer would possess.

1) Bigger is better - make your fonts bigger than those for a desktop app. Developers think that because of the limited real estate on a PDA they'll make things smaller. Wrong! The end user can't SEE it in a mobile environments.

2) There are colors other than black and white - use them to your advantage because of the limited real estate of a PDA.

3) Less is more - it's better to spread information between numerous forms than to cram everything into a single form.

4) Do it for them - the less input the end user has to do, the better. Using a stylus or small keyboard is not easy. Provide default values, combo/listboxes, easy movement between forms, predefined text strings the user can select, etc.

5) Keep users away from dangerous buttons - it's easier to make mistakes on a PDA than on a desktop, due to the limited real estate and different end-user conditions.

6) Does it work there? - test your app in the intended environment. You'll be surprised how difficult it might be to use.

7) What happens if the batteries die or your connection fails? - good questions to worry about.

8) Don't just convert your desktop interface to a PDA. Build a new one from scratch for a PDA - desktop interfaces just don't work as well on a PDA. They are different animals.

9) Hey, this isn't a PC! - PDAs have smaller screens, no mouse, slower processors, no hard drive, less memory and they run on batteries. Remember that.

10) The .NET Compact Framework isn't just a mini .NET Framework - it has been significantly trimmed (from 30 meg to 3 meg), and therefore coding techniques (and commands) used in the full Framework might not work in the Compact Framework. Beware!

As an aside for MV developers - mv.NET will not work on a PDA. It's too big. I spoke a long time ago with Dave Cooper (of BlueFinity) about making a "Compact mv.NET" and he told me that the way they had developed mv.NET (.NET remoting) precluded them for developing it for a PDA. (That's why I chose web services as the way to go.)

Sholom
.

Loading