Class: VisualRegion

• Inheritance
• Description
• Instance protocol
  • accessing
  • change & update
  • initialization
  • private
  • queries
  • shape computation
• Examples

Inheritance:

   Object
   |
   +--GraphicsMedium
      |
      +--DisplaySurface
         |
         +--SimpleView
            |
            +--VisualRegion

Package:

stx:libview2

Category:

Views-Special

Version:

rev: 1.15 date: 2023/07/06 15:10:37

user: cg

file: VisualRegion.st directory: libview2

module: stx stc-classLibrary: libview2

Description:

VisualRegion is a passive visual component which provides a rectangular or elliptical
shape. It can take an arbitrary border line thicknesses and can be defined as opaque
with a background color or non opaque.

Notice:
  This is an ST-80 compatibility class, provided to aid porting
  of ST-80 or VisualWorks code;
  it may be incomplete or incompatible to the corresponding ST-80 class. 
  If you encounter any incompatibilities, please forward a note 
  describing the incompatibility verbal (i.e. no code) to the ST/X team.

copyright
COPYRIGHT (c) 1997 by Claus Gittinger
             All Rights Reserved

This software is furnished under a license and may be used
only in accordance with the terms of that license and with the
inclusion of the above copyright notice.   This software may not
be provided or otherwise made available to, or used by, any
other person.  No title to or ownership of the software is
hereby transferred.

Instance protocol:

 isElliptical

get the outline of the region; elliptical or rectangle

 isElliptical: aBoolean

set the outline of the region; elliptical or rectangle

 isOpaque

return true, if the object fully covers its frame (i.e. is rectangular
and has no 'holes'.
Here, get the opaque mode concerning the inner background of the region

 isOpaque: aBoolean

set opaque mode concerning the inner background of the region

 lineWidth: aNumber

set the border drawing width in pixels

 setLineWidth: aNumber

set the line drawing width in pixels without recomputation of the shape

 sizeChanged: how from: oldExtentOrNil

my bounds have changed;
must compute a new shape, when size is changed

 initialize

setup default configuration

 layoutChanged

recompute shape and change to invalidate

 specClass

returns my spec class (for UI editor)

 computeShape

computes 2 forms, one for the border, the other for the inside area. The border
form is borderwidth*2 pixels larger. Each form gets filled with an ellipse of
1-pixels, to define the shapes (take a look at the XShape spec, for more info)

Examples:

    |top s1 s2 s3 s4 v1 rd i vh|

    top := StandardSystemView new extent:250@250.

    rd := true.

    v1 := View origin:25@25 extent:50@50 in:top.
    v1 viewBackground:(Color blue).
    v1 cursor:(Cursor thumbsUp).
    vh := ValueHolder new.
    vh onChangeSend:#value to:[ v1 viewBackground:vh value. v1 clear ].
    vh inspect.

    s1 := VisualRegion origin:10@10 extent:30@30 in:top.
    s1 lineWidth:0.
    s1 viewBackground:(Color gray:90).
    s1 isElliptical:rd.
    s1 middleButtonMenu:(PopUpMenu labels:#('foo' 'bar')).

    s2 := VisualRegion origin:60@10 extent:30@30 in:top.
    s2 viewBackground:(Color green).
    s2 lineWidth:1.
    s2 isElliptical:rd.

    s3 := VisualRegion origin:10@60 extent:100@30 in:top.
    s3 viewBackground:(Color gray:70).
    s3 lineWidth:0.
    s3 isOpaque:false.
    s3 isElliptical:rd.

    s4 := VisualRegion origin:60@60 extent:60@30 in:top.
    s4 viewBackground:(Color red).
    s4 lineWidth:3.
    s4 isOpaque:false.
    s4 isElliptical:rd.
    s4 middleButtonMenu:(PopUpMenu labels:#('foo1' 'bar1')).

    i := InputView origin:70@60 extent:60@30 in:top.
    i middleButtonMenu:(PopUpMenu labels:#('foo2' 'bar2')).

    top open