Smalltalk/X Webserver

Documentation of class 'VisualRegion':

Class: VisualRegion

Inheritance
Description
Instance protocol
Examples

Inheritance:

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

Package:: stx:libview2

Category:: Views-Special

Version:: rev: 1.11 date: 2015/05/05 11:14:10; 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.

Instance protocol:

accessing

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

change & update

sizeChanged: how: must compute a new shape, when size is changed

initialization

initialize: setup default configuration

private

layoutChanged: recompute shape and change to invalidate

queries

specClass

shape computation

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)

some regions; the blue one has its own cursor, the light-grey and red ones havea popupMenu, however, the red one is almost completely covered by an invisible inputView which provides its own menu (only the far left edge of the red region shows the red-menu)

    |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