A+ Reference: The Action Display Class

# The Action Display Class

> The action display class is for the display of any slotfiller variables. The display consists of a title area above a collection of label areas, one for each symbolic index. When the slotfiller has a callback function and the left button is clicked with the mouse cursor on a label, the callback function is called with the path argument p equal to the symbolic index of the pressed label, and the new-value argument d equal to the slotfiller itself. The value of the slotfiller does not actually change; the callback occurs because an assignment of the form:

>          (pØd)ûpØd

> is automatically generated when an action item is selected.

> The slotfiller values do not affect the display of an action object, but can be used by the programmer to identify the actions to be taken when the labels are pressed.

> The label areas in action objects are treated in exactly the same way as label areas in objects bound to the slot display class. The label areas cannot be edited. There are no value areas.

> The label areas that appear in the display and their arrangement can be controlled by the setting of the geometry attribute; see "The Geometry Attribute". All label areas specified for display by this attribute are completely displayed; action displays never have scrollbars.

Visual Representation

>          acû(`open `close `save;(;;))
>          `ac has (`class;     `action;
>                   `shelltitle;"ShellTitle";
>                   `title;     "WidgetTitle")
>          show `ac

For information about a widget element, click the left mouse button with tip of the pointer index finger on it. Point inside the frame but outside the widget for attributes governing overall size, position, etc.

The element you are pointing at is named in the status message area at the bottom of the window.

(Clicking the middle mouse button instead displays this information in a new browser.)

Attributes

> See the "Display Attributes" chapter for details concerning all the attributes that apply to objects in the action display class, as well as lists of colors and fonts. The keys in the Table of All Display Attributes that pertain to this class are N, ALL, CNFT, NFT, and TOP.

> The attributes that are meaningful for the action display class (other than the print... attributes) are:

> acceptfocus
> active
> ancestors
> arrowdown
> arrowkeys
> arrowleft
> arrowlist
> arrowright
> arrowup
> at
> atsector
> b
> bg
> bound
> C
> class
> clear
> deiconized
> doc
> downto
> dynamic
> eval
> evaluate
> exit
> extent
> f1-f12
> fg
> fkeys
> focus
> followers
> followertree
> foot
> font
> freeze
> fullscreen
> geometry
> h
> H
> has
> head
> hide
> hl
> hlthickness
> icon
> iconic
> iconized
> icontitle
> incurrentworkspace
> is
> justify
> l
> label
> labelfg
> labelfont
> leader
> leftto
> literal
> lower
> mapped
> naturalsize
> notify
> outofcurrentworkspace
> parent
> pin
> preset
> primary
> protect
> protected
> r
> R
> raise
> realize
> refresh
> request
> resize
> resizeable
> rightto
> script
> selected
> sensitive
> set
> settings
> shadowthickness
> shell
> shelltitle
> show
> state
> stateself
> syncshow
> t
> tabfrom
> tablist
> tabto
> title
> titlefg
> titlefont
> titlejustify
> upto
> vcol
> vcols
> verify
> vrow
> vrows
> w
> W
> ws
> x
> X
> xs
> y
> Y
> ys
> yx
> YX
> yxs (Point the mouse cursor to an attribute to display a short description at the bottom of the screen)