Apple Newton Programmer’s Newton 2.0 (for Newton 2.0) - Manual (Page 263)

C H A P T E R 7
Controls and Other Protos
Scroller Protos 7-3
■ The protoUpDownScroller is centered on the right side of a view and
provides vertical scroll arrows. For more information about the slots and
methods for this scroller, see “protoUpDownScroller” (page 6-5) in Newton
Programmer’s Reference. Figure 7-3 shows an example of a
protoHorizontal2DScroller view.
Figure 7-3 A protoUpDownScroller view
■ The protoHorizontalUpDownScroller is centered at the bottom of a
view and provides vertical scroll arrows. For more information about the slots
and methods for this scroller, see “protoHorizontalUpDownScroller” (page 6-6)
in Newton Programmer’s Reference. Figure 7-4 shows an example of a
protoHorizontalUpDownScroller view.
Figure 7-4 A protoHorizontalUpDownScroller view
Implementing a Minimal Scroller 7
To implement a minimal scroller, all that you have to define is a
ViewScroll2DScript method in your scroller template. This method is
called whenever the user taps one of the scroll arrows in the scroller view. Your
ViewScroll2DScript method must perform the actual scrolling of the contents
of some other view, which you usually do by calling the SetOrigin method.
For more information on the ViewScroll2DScript method, see
“ViewScroll2DScript” (page 6-3) in Newton Programmer’s Reference. For
more information on the
SetOrigin method, see “SetOrigin” (page 2-48) in
Newton Programmer’s Reference.
Automatic Arrow Feedback 7
All of the scroller protos can provide visual feedback to the user indicating that
there is more information to see. This feedback is handled automatically for your if
you provide three additional slots in your scroller template:
scrollRect ,