Page 1
Page 2
This time I decided to take a break
from Windows CE certification to look at something fun I
discovered while updating one of my applications. I hope
everyone has at least taken a quick peak at the Veritest
website to find out how to get certified.
Watch Those Combo Boxes…
You might have noticed that it has
been a few months without a report. Well, I've been working
hard on a new version of one of my applications (and eating
turkey, shopping for Christmas presents, etc…). I ran
into a challenge and realized that, once again, I need to
improve a old standard user interface to make it easier
to use on the PocketPC.
Have you ever seen an application that
used combo boxes with too many elements? You may be asking,
"What is he getting at?" I mean applications where
there are dozens of items that appear in a combo box. For
example, have you ever have an application that includes
a list of all 50 states? A combo box is literally a drag
(or at least a scroll) to use. You need to scroll and scroll
to find the right item. How many times have you accidentally
tapped "off" the scroll bar only to have the wrong
selection and need to start over? Programmers use combo
boxes to save some real estate on the screen and they are
great for short lists of items. However, we need to make
it easier for our users when the list is longer. Who wants
to scroll forever to get to the one element you need? You
can see an example of what I'm talking about in Figure
1. This shows one of Microsoft's setup programs with
a very long combo box containing all the possible locales
you can select.
Figure 1
By now, you probably realize that I
don't bring up a problem without at least contemplating
a solution. In most programs on a desktop a user can jump
quickly in a combo box by typing a character. This doesn't
work on the Pocket PC but I wanted to provide users a way
of "jumping" down a list of selections to minimize
the amount of scrolling needed. The PocketPC already has
a program that offers the same capabilities: Contacts.
A user can quickly jump between sections of their contact
list by tapping a command button with a set of three letters.
I'll use this as a template to my own replacement for a
combo box.
Building the Dialog…
Figure 2 shows the interface
for my new control. The screen is fairly simple; it consists
of a row of buttons with three letters on each (identical
to the contacts application), a done button to accept our
choice, and a cancel to ignore our choice.
Figure 2
The application I'm writing is related
to role-playing games (what else!) and I need to be able
to select from lists items like spells and weapons. These
may change over time (as the user's game master creates
new ones or new supplements come out) and I could not hard
code the items I would add to selection lists. Thus, the
control I created uses a text file to define the items the
user can select from. An example is shown in Listing
1. The first element on a line is the key, or name,
to display in the list. Addition information is stored in
a colon-separated list. This is the example I will use to
demonstrate this technique. The file is called Students.def.
Able:Chicago:312-555-1222:Loves
Cats
Adam:Milwaukee:214-555-1211:Lives at home
Alex:Sleepy Hollow:847-555-3456:Enjoys Snowball fights!
Carl:West Dundee:847-555-1000:Loves computers, super Geek!
Carla:Michigan:None:Carl's Sister.
Chandler:Arizona:555-555-5555:It is hot!
Elizabeth:City:555-555-4000:Couldn't think of anything.
Freddy:North Carolina:454-555-4545:None
George:Test:555-555-5555:None
Jennifer:Test:555-555-5555:None
Jessica:Test:555-555-5555:None
Jimmy:Test:555-555-5555:None
Kathy:Test:555-555-5555:None
Liz:Test:555-555-5555:None
Manuel:Test:555-555-5555:None
Morgan:Test:555-555-5555:None
Nicole:Test:555-555-5555:None
Paul:Test:555-555-5555:None
Roger:Test:555-555-5555:None
Sam:Test:555-555-5555:None
Terry:Test:555-555-5555:None
Tim:Test:555-555-5555:None
Tom:Test:555-555-5555:None
William:Test:555-555-5555:None
Woodberry:Test:555-555-5555:None
X Man:Test:555-555-5555:None
Zack:Test:555-555-5555:None
Listing 1
Next Page