Controls and Other Protos

Time Protos

ChangedSlider: func()

begin
SetVolume(viewValue);
:SysBeep();
end,

...}

The example above initializes the slider gauge to indicate the current system
volume, which it retrieves from the user configuration that is maintained by the
Newton System Software. The range of allowable volume values is from

0

(the default for

minValue

) to

4

.

Whenever the user moves the slider and lifts the pen, the

viewValue

slot is

updated and the

ChangedSlider

method is called. In the example, the

ChangedSlider

method resets the system volume to the new value chosen by

the user and sounds a beep to provide the user with audible feedback.

For more information on the

protoSlider

and the

ChangedSlider

method,

see "protoSlider" (page 6-33) in Newton Programmer's Reference.

Time Protos

7

You can use the time protos to allow the user to set time and date values. There are
four time protos:

The

protoDigitalClock

time proto displays a digital clock with which the

user can set a time value. For more information about the slots and methods for
this proto, see "protoDigitalClock" (page 6-38) in Newton Programmer's
Reference. Figure 7-21 shows an example of a

protoDigitalClock

view.

A

protoDigitalClock

view

The

protoNewSetClock

time proto displays an analog clock with which the

user can set a time value. For more information about the slots and methods for
this proto, see "protoNewSetClock" (page 6-40) in Newton Programmer's
Reference. Figure 7-22 shows an example of a

protoNewSetClock

view.