Return the computed virtual content height, excluding this Group's outer

Area contribution.

LONG; get only. Supply writable IPTR getter storage.

Group stores this extent during layout. Read after valid setup, min/max

calculation and layout; the initial zero is not a measured content size.

The viewport is the inner visible box, not this value. Built-in virtual

layout and custom LayoutHook paths calculate extents differently; a

custom hook writes Width/Height back in its layout message. No local

setter is implemented.

Declared initialization flag without an implementation in the AROS

Virtgroup/Group classes.

BOOL initialization declaration in the header; no local consumer, setter

or getter.

Setting FALSE does not disable Group virtual mouse/tick autoscroll.

Setting TRUE does not enable an additional input mode. Unrecognized

getters may fall through to children through Group; that does not

establish local support. No default behavior should be inferred from

this unused declaration.

Set or query the horizontal offset into virtual content. Zero selects

the leading edge.

LONG; implemented set/get, with int setter temporaries and WORD

layout-clamping temporaries. Initialization tags are not consumed by

Group.

A changed setter stores the converted value and relayouts children. When

drawable, it hides/shows children and requests a scroll redraw. Layout

clamps offsets to zero through content extent minus viewport extent

(with zero as the minimum), then uses Group_Forward FALSE for

corrections. This does not suppress notifications. The getter returns

the stored value. Use setup and valid child min/max state before

setting; avoid setting virtual offsets on nonvirtual groups.

Layout copies the stored LONG offset into a WORD before clamping;

out-of-range input can wrap instead of saturating. Layout can reenter

the setter while correcting offsets. A setter return is not a

child-layout success report. Initialization support advertised by the

header is absent in this implementation.

Set or query the vertical offset into virtual content. Zero selects the

leading edge.

LONG; implemented set/get, with int setter temporaries and WORD

layout-clamping temporaries. Initialization tags are not consumed by

Group.

A changed setter stores the converted value and relayouts children. When

drawable, it hides/shows children and requests a scroll redraw. Layout

clamps offsets to zero through content extent minus viewport extent

(with zero as the minimum), then uses Group_Forward FALSE for

corrections. This does not suppress notifications. The getter returns

the stored value. Use setup and valid child min/max state before

setting; avoid setting virtual offsets on nonvirtual groups.

Layout copies the stored LONG offset into a WORD before clamping;

out-of-range input can wrap instead of saturating. Layout can reenter

the setter while correcting offsets. A setter return is not a

child-layout success report. Initialization support advertised by the

header is absent in this implementation.

Return the computed virtual content width, excluding this Group's outer

Area contribution.

LONG; get only. Supply writable IPTR getter storage.

Group stores this extent during layout. Read after valid setup, min/max

calculation and layout; the initial zero is not a measured content size.

The viewport is the inner visible box, not this value. Built-in virtual

layout and custom LayoutHook paths calculate extents differently; a

custom hook writes Width/Height back in its layout message. No local

setter is implemented.

Group.mui

Create a Group with virtual-content layout enabled. The only local

override is construction: prepend Group_Virtual TRUE and then process

caller tags. A later Group_Virtual FALSE can override that default.

Virtgroup has no additional instance storage, local disposal or local

scrolling implementation.

All child ownership, setup/cleanup, clipping, layout hooks, offset

storage and mouse-driven edge scrolling belong to Group. Scrollbars are

not created automatically. Group saves content minima while exposing a

small viewport minimum; width/height getters report computed virtual

content extents, not the viewport size.

Construction returns the Group constructor result, including NULL on

failure. All other methods delegate unchanged to Group. Use a valid

connected/setup object and completed min/max calculation before changing

offsets: Group's setter can call Layout even when the object is not

drawable.

In virtual mode Group tracks mouse buttons and ticks for edge

autoscroll. Virtgroup_Input does not control that behavior in this

implementation.

Left/Top are implemented by Group's setter and getter but not its

initialization-tag parser, despite the header marking them

initialize/set/get. Initial offsets remain the zero-initialized values.

Width/Height become meaningful after layout. Private MinWidth/MinHeight

expose saved content minima; they are internal interfaces, not public

scrolling controls.