Apple Newton Programmer’s Newton 2.0 (for Newton 2.0) - Manual (Page 378)

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Recognition: Advanced Topics
10-2 About Advanced Topics in Recognition
applications to change these system-wide settings. Instead, individual views can
customize their own recognition behavior by using a
recConfig frame or
recToggle view to override these inherited values locally.
In practice, most views’ recognition behavior is defined by a combination of
inherited and overridden values. For example, because most users tend not to
change the speed at which they write, it’s common for views to use inherited values
for the
timeoutCursiveOption slot, which specifies the relative delay required
to consider a group of input strokes complete. At the same time, individual views
may customize certain recognition settings by overriding values that would
otherwise be inherited from the system’s user configuration data. For example, a
view can use a
recConfig frame to disable the automatic addition of new words
to the user dictionary.
A view based on the protoRecToggle system prototype provides another way to
override inherited recognition settings. This view provides a picker that allows the
user to change recognition settings easily. Each view controlled by this picker must
provide a
_recogSettings slot that the picker sets according to the user’s
current choice of recognition settings. The value in the _recogSettings slot
overrides values inherited from the system’s user configuration data.
Your application supplies only one _recogSettings slot for each recToggle
view it provides. Because views use parent inheritance to find a _recogSettings
slot, a single recToggle view and a single _recogSettings slot can control
the recognition behavior of one view or multiple views, depending on the
_recogSettings slot’s position in the view hierarchy. For more information, see
“Creating the _recogSettings Slot” beginning on page 10-20.
You can also provide an optional RecogSettingsChanged method in the
_parent chain of any view controlled by the recToggle view. If a
RecogSettingsChanged method is provided, the recToggle view sends this
message to self when the user chooses an item in the recToggle picker.Your
RecogSettingsChanged method can perform any application-specific task that
is appropriate; typically, this method reconfigures recognition settings in response
to the change in the
recToggle view’s state.
Finally, any view can provide an optional recConfig frame that specifies the
view’s recognition behavior at the local level.
Although recConfig frames have thus far been presented as simply an alternate
interface to the recognition system, they are actually used internally by the system
to represent the recognition behavior of each view. When the user writes, draws, or
gestures in a view, the system builds a
recConfig frame that specifies the precise
settings of all the recognizers needed for the view. If you supply a recConfig
frame for the view, the recConfig frame that the system builds is based on the
recConfig frame you have supplied and any recognition-related user preferences
that may apply.