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Apple Newton Programmer’s Newton 2.0 (for Newton 2.0) User Manual

Page 147

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C H A P T E R 4

NewtApp Applications

About the NewtApp Framework

4-9

Note that the header bar contains the Action and Filing buttons on its right side.
These buttons appear on the header bar to prevent any ambiguity regarding the
entry to be acted upon by those buttons.

In addition, the header bar contains a Title and icon on the left. When the icon is
tapped, the Information slip appears, as shown in Figure 4-5. This slip is created
from a

newtInfoBox

proto and displays an informational string, which it obtains

from the

description

slot of the dataDef. See Chapter 5, “Stationery,” for more

information about dataDefs.

Figure 4-5

An Information slip

It is at the entry view level of your application that the specific slots for accessing
and displaying data in your application soup are set up. The target entry, which is
the entry to be acted on, is set in the entry view. The target view is then created by
the entry view; the view in which the data in that entry appears. Finally, the data
cursor is created by the entry view and is used to access the entries.

The entry view protos also contain important methods that act on individual
entries. These methods include functionality for managing and changing existing
data in the soup, such as the

FlushData

method.

About the Slot View Protos

4

The slot view protos retrieve, display, edit, and save changes to any type of data
stored in the slots of your application soup’s entry frame.

Unless they are contained by either a

newtEntryView

or a

newtFalseEntryView

, the slot views do not work. This is because the

entry views are responsible for setting references to a specific entry. These
references are used by the slot view to display data.

Slot views exist in two varieties: simple slot views and labelled input-line slot
views. Both kinds of slot views are tailored to display and edit a particular kind of