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Implementing a simple button 7 – Apple Newton Programmer’s Newton 2.0 (for Newton 2.0) User Manual

Page 270

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C H A P T E R 7

Controls and Other Protos

7-10

Button and Box Protos

Implementing a Simple Button

7

To provide a simple button in your application, pick a button proto to use, set the
appropriate slots in the button object, and (in most cases) define one or more
scripts for the button.

The following is an example of a template that includes

protoTextButton

:

aButton := {...

_proto: protoTextButton,

viewFont: ROM_fontSystem12Bold,

text: "My Button",

ButtonClickScript: func()

Print("ouch!");

// a handy way to fit a button around a string

ViewSetupFormScript: func()

viewbounds := RelBounds(10, 60,

StdButtonWidth(self.text), 13);

...}

The above example creates the following button on the Newton screen:

When the user taps this button in the Inspector, “ouch” is printed to the Inspector.

You implement a picture button with a similar template, as shown in the
following example:

pictButton := {...

_proto: protoPictureButton,

icon: namesBitmap,

viewBounds: SetBounds( 2, 8, 34, 40 ),

ButtonClickScript: func()

cardfile:Toggle()

...}

For more information on implementing specific button and box protos, see “Button
and Box Protos” (page 7-6) in Newton Programmer’s Reference.