• Character selection errors are reduced, since the user does not have to choose
between, say, ă and ǎ, as in more general methods. A particular language or other
context seldom contains both characters.
The virtual key idea is easy and quick to implement. Thus, it can be applied even on
an individual basis, to create a convenient input form for someone’s personal needs
and preferences. On the other hand, this approach is normally application dependent:
the method needs to be implemented separately for each data entry form. For imple-
mentation issues, see “Character Input and Output” in Chapter 11.
Along similar lines, we could use virtual keys that correspond to writing several char-
acters. If user input is expected to contain some fixed strings rather often, a form de-
signer can set up keys (buttons) that add those strings. This is particularly useful if the
strings contain characters that cannot be directly typed on users’ keyboards.
We often need program-specific ways of entering characters from a keyboard, either
because there is no key for a character we need or there is but it does not work. The
program involved might be part of system software, or it might be an application pro-
gram. We describe here some typical cases.
Copying via the Clipboard
In typical computer systems, you can copy data from one program to another through
an internal storage area called the clipboard. On Windows, you can usually highlight
text with the mouse or select a piece of text otherwise, and then press Ctrl-C to copy,
click on a location in another window, and press Ctrl-V to paste a copy of the text there.
This also works inside a program of course, so you can use it to create copies of a
character or a string.
This feature is well known by most users and often very convenient, though it cannot
be the primary method of writing text. You can however copy characters from web
pages or from text documents specifically designed for use as “cliptext.”
Often this technique has the property of copying text formatting along with the text. If
you copy bold 16-point Verdana text from Excel to Word, you get 16-point Verdana
text, not text in the normal font as defined by your Word settings or template. This
might be desirable, but more often, it is a problem. Moreover, constructs like hypertext
links may get copied along with the text. To make sure that only the plain text is in-
serted, you can first paste the text in Notepad, select it again there, press Ctrl-C, and
paste in the desired destination.
Program Commands | 83
may have command menus for inserting characters, so that characters are
identified by some names or glyphs. At the simplest, you just select a command and a
subcommand from a menu. Usually it is more complicated, to allow the insertion of
more characters that can conveniently be included into a command menu.
Insertion menu in Thunderbird
In Mozilla Thunderbird, when composing an email message, you can select Insert →
Characters and symbols. This opens a small window, as in Figure 2-7. There, you can
select a class of characters by clicking on one of the radio buttons. This affects the drop-
down menu under the buttons. For example, when Common Symbols is selected, the
Character drop-down menu contains a collection of Latin 1 special characters (other
than letters), such as © and ±.
Such an input method is intuitively easy and can be found and used by a user even
without any documentation. On the other hand, it is rather clumsy, since any insertion
requires several steps.
Symbol (character) insertion menu in MS Word
In MS Word, you can use the command Insert → Symbol to invoke an auxiliary
window, which has two modes of operation. In the default mode, Symbols, you can
select a character from a table, as explained in the section “Character Maps later in this
chapter. You enter the second mode by clicking on Special Characters. There, you can
pick up a character from a short list, as shown in Figure 2-8. The list also contains
information about shortcut keys for the characters, so it can be used to check such
Figure 2-7. Character insertion window in Thunderbird
84 | Chapter 2: Writing Characters