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Where to go from here 9 – Apple Newton Programmer’s Newton 2.0 (for Newton 2.0) User Manual

Page 352

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C H A P T E R 9

Recognition

9-10

About the Recognition System

multiple bits in the input mask to produce a particular behavior. You can use a

recConfig

frame to set individual bits in the input mask, allowing you to control

aspects of recognition behavior that view flags do not.

Some features of the recognition system require the use of a

recConfig

frame.

For example, to create a view that provides single-letter input areas suitable for
accepting pen input in a crossword puzzle application, you must supply a

recConfig

frame that provides an

rcGridInfo

frame. The system-supplied

rcGridInfo

frame is used to specify the location of one or more single-letter

input views.

This chapter focuses on the use of view flags to configure recognition. The use of

recConfig

frames is described in Chapter 10, “Recognition: Advanced Topics.”

System-supplied

recConfig

frames are described in “System-Supplied recConfig

Frames” (page 8-18) in Newton Programmer’s Reference.

View Flags vs. RecConfig Frames

9

In most cases, view flags provide the easiest and most efficient way to configure
the recognition system. Although

recConfig

frames provide more flexible and

precise control over the configuration of recognition behavior, they require more
effort to use correctly.

It is recommended that you use view flags to configure recognition unless you need
some special recognition behavior that they cannot provide. Examples of such
behavior include constraining recognition on a character-by-character basis,
implementing customized forms of deferred recognition, and defining baseline or
grid information.

The rest of this chapter discusses configuration of the recognition system only in
terms of the view flag model. You need to read this material even if you plan to use

recConfig

frames in your application, because the description of

recConfig

frames in Chapter 10, “Recognition: Advanced Topics,” assumes an understanding
of the view flag model upon which these frames are based.

Where to Go From Here

9

If you’re anxious to begin experimenting with view flags, you can skip ahead to
“Using the Recognition System” beginning on page 9-21 and test the effects of
various flags using the viewFlags sample application provided with Newton
Toolkit. However, it is recommended that you read the rest of this section before
attempting to work with the recognition system.