added conversion to alignmentOrigin and another access method.
"
COPYRIGHT (c) 1995 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.
"
Layout subclass:#LayoutOrigin
instanceVariableNames:'leftFraction topFraction leftOffset topOffset'
classVariableNames:''
poolDictionaries:''
category:'Graphics-Geometry'
!
!LayoutOrigin class methodsFor:'documentation'!
copyright
"
COPYRIGHT (c) 1995 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.
"
!
documentation
"
This class is provided to make porting of existing ST-80 applications
easier. Instances can be used to control the geometry of a subview, within
its superview. It provides the same functionality as a relative origin
combined with insets.
A layoutOrigin controls the origin of a subcomponent, given a fractional
component and an offset component.
Notice:
this class was implemented using protocol information
from alpha testers - it may not be complete or compatible 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.
[author:]
Claus Gittinger
[see also:]
View
LayoutFrame AlignmentOrigin Layout
Rectangle Point
"
!
examples
"
Although the examples below use a button as component,
they work of course with any type of subview ....
using a LayoutOrigin, to arrange for
the TOPLEFT of a component be positions
at the center (i.e. buttons origin at:0.5 @ 0.5):
[exBegin]
|top button|
top := StandardSystemView new.
top extent:300@300.
button := Button label:'component'.
top add:button in:(LayoutOrigin new
leftFraction:0.5;
topFraction:0.5).
top open
[exEnd]
like above, but adds an additional offset:
(i.e. center of button at:0.5 @ 0.5 OFFSET by 10 @ 20):
[exBegin]
|top button|
top := StandardSystemView new.
top extent:300@300.
button := Button label:'component'.
top add:button in:(LayoutOrigin new
leftFraction:0.5;
topFraction:0.5;
leftOffset:10;
topOffset:20).
top open
[exEnd]
"
! !
!LayoutOrigin class methodsFor:'instance creation'!
fractionalFromPoint:aPoint
"given a point, create a layoutOrigin representing the same
relative origin."
^ (self new) leftFraction:aPoint x topFraction:aPoint y
"
LayoutOrigin fractionalFromPoint:0.5@0.5
"
!
fromPoint:aPoint
"return a new LayoutOrigin from aPoint.
If the coordinates are between 0 and 1, take
them as fractional parts (relative to superview).
Otherwise, treat them as absolute offsets."
|x y layout|
x := aPoint x.
y := aPoint y.
layout := self new.
((x between:0 and:1)
and:[y between:0 and:1]) ifTrue:[
layout leftFraction:x topFraction:y
] ifFalse:[
layout leftOffset:x topOffset:y
].
^ layout
"
LayoutOrigin fromPoint:100@100
LayoutOrigin fromPoint:0.5@0.5
LayoutOrigin fromPoint:0.5@100
"
!
offsetFromPoint:aPoint
"given a point, create a layoutOrigin representing the same
absolute (pixel) origin."
^ self new leftOffset:aPoint x topOffset:aPoint y
"
LayoutOrigin offsetFromPoint:100@100
"
! !
!LayoutOrigin methodsFor:'accessing'!
leftFraction
"return leftFraction"
^ leftFraction
!
leftFraction:something
"set leftFraction"
leftFraction := something.
!
leftFraction:something offset:o
"set leftFraction and offset"
leftFraction := something.
leftOffset := o
!
leftFraction:lF offset:lO topFraction:tF offset:tO
"set leftFraction, leftOffset, topFraction and topOffset"
leftFraction := lF. leftOffset := lO.
topFraction := tF. topOffset := tO.
"Created: 18.4.1997 / 20:07:15 / cg"
!
leftFraction:newLeft topFraction:newTop
"set leftFraction and topFraction"
leftFraction := newLeft.
topFraction := newTop.
!
leftInset:pixels
"set leftOffset for an inset at the left"
leftOffset := pixels.
"Created: 26.5.1996 / 17:38:55 / cg"
"Modified: 26.5.1996 / 17:42:16 / cg"
!
leftOffset
"return leftOffset"
^ leftOffset
!
leftOffset:something
"set leftOffset"
leftOffset := something.
!
leftOffset:newLeft topOffset:newTop
"set leftOffset and topOffset"
leftOffset := newLeft.
topOffset := newTop.
!
topFraction
"return topFraction"
^ topFraction
!
topFraction:something
"set topFraction"
topFraction := something.
!
topFraction:something offset:o
"set topFraction and offset"
topFraction := something.
topOffset := o
!
topInset:pixels
"set topOffset for an inset at the top"
topOffset := pixels.
"Created: 26.5.1996 / 17:39:00 / cg"
"Modified: 26.5.1996 / 17:42:12 / cg"
!
topOffset
"return topOffset"
^ topOffset
!
topOffset:something
"set topOffset"
topOffset := something.
! !
!LayoutOrigin methodsFor:'converting'!
asAlignmentOrigin
"return an equivalent alignmentOrigin"
^ AlignmentOrigin new
leftFraction:leftFraction offset:leftOffset;
topFraction:topFraction offset:topOffset;
leftAlignmentFraction:0 topAlignmentFraction: 0;
yourself
"Created: 18.4.1997 / 20:08:14 / cg"
!
fromLiteralArrayEncoding:encoding
"read my values from an encoding.
The encoding is supposed to be of the form:
(#LayoutOrigin orgOffsX relOrgX orgOffsY relOrgY)
This is the reverse operation to #literalArrayEncoding."
leftOffset := encoding at:2.
leftFraction := encoding at:3.
topOffset := encoding at:4.
topFraction := encoding at:5.
"
LayoutOrigin new fromLiteralArrayEncoding:#(#LayoutOrigin 70 0 2 0)
"
!
literalArrayEncoding
"encode myself as an array, from which a copy of the receiver
can be reconstructed with #decodeAsLiteralArray.
The encoding is:
(#LayoutOrigin orgOffsX relOrgX orgOffsY relOrgY)
"
^ Array
with:self class name asSymbol
with:leftOffset
with:leftFraction
with:topOffset
with:topFraction
"
LayoutOrigin new fromLiteralArrayEncoding:#(#LayoutOrigin 70 0 2 0)
(LayoutOrigin new leftOffset:10; leftFraction:0.2;
topOffset:20; topFraction:0.4) literalArrayEncoding
"
"Modified: 1.9.1995 / 02:43:48 / claus"
"Modified: 22.4.1996 / 13:00:21 / cg"
! !
!LayoutOrigin methodsFor:'initialization'!
initialize
leftOffset := topOffset := 0.
leftFraction := topFraction := 0.
! !
!LayoutOrigin methodsFor:'printing & storing'!
displayString
^ (self class name) , '('
, 'l: ' , leftFraction displayString
, '+' , leftOffset displayString
, ' t: ' , topFraction displayString
, '+' , topOffset displayString
, ')'
! !
!LayoutOrigin methodsFor:'queries'!
isLayoutOrigin
"return true, if this is a layoutOrigin"
^ true
!
origin
^ leftFraction asFloat @ topFraction asFloat
!
rectangleRelativeTo:superRectangle preferred:prefRect
"compute the rectangle represented by the receiver,
given the superViews rectangle and the views preferredExtent."
|x y|
leftOffset isNil ifTrue:[
x := 0
] ifFalse:[
x := leftOffset
].
topOffset isNil ifTrue:[
y := 0
] ifFalse:[
y := topOffset
].
leftFraction notNil ifTrue:[
x := x + (superRectangle width * leftFraction)
].
topFraction notNil ifTrue:[
y := y + (superRectangle height * topFraction)
].
^ Rectangle left:x top:y extent:prefRect extent
"
|superRect lO|
superRect := 0@0 corner:100@100.
lO := (LayoutOrigin new).
lO leftFraction:0.5;
topFraction:0.5.
lO rectangleRelativeTo:superRect preferred:(0@0 corner:30@30)
"
"Modified: 8.5.1996 / 20:58:53 / cg"
! !
!LayoutOrigin class methodsFor:'documentation'!
version
^ '$Header: /cvs/stx/stx/libview2/LayoutOrigin.st,v 1.16 1997-04-18 18:10:47 cg Exp $'
! !