"
 COPYRIGHT (c) 1989 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.
"

Scroller subclass:#HorizontalScroller
       instanceVariableNames:''
       classVariableNames:''
       poolDictionaries:''
       category:'Views-Interactors'
!

HorizontalScroller comment:'

COPYRIGHT (c) 1989 by Claus Gittinger
              All Rights Reserved

the scroller part of a horizontal scrollbar

$Header: /cvs/stx/stx/libwidg/HorizontalScroller.st,v 1.5 1994-08-07 13:22:36 claus Exp $
written spring/summer 89 by claus
'!

!HorizontalScroller methodsFor:'initialization'!

initialize
    super initialize.
    moveDirection := #x
! !

!HorizontalScroller methodsFor:'accessing'!

thumbOrigin:newOrigin
    "set the thumbs origin (in percent)"

    |realNewOrigin oldFrame oldLeft oldRight thumbLeft thumbRight
     tH tW delta top|

    ((newOrigin + thumbHeight) > 100) ifTrue:[
        realNewOrigin := 100 - thumbHeight
    ] ifFalse: [
        realNewOrigin := newOrigin
    ].
    (realNewOrigin > 100) ifTrue:[
        realNewOrigin := 100
    ] ifFalse: [
        (realNewOrigin < 0) ifTrue:[
            realNewOrigin := 0
        ]
    ].
    (realNewOrigin = thumbOrigin) ifFalse:[
        thumbOrigin := realNewOrigin.

        shown ifTrue:[
            oldFrame := thumbFrame.
            self computeThumbFrame.
            (thumbHeight = 100) ifTrue:[^ self].

            (thumbFrame ~~ oldFrame) ifTrue:[
                oldFrame isNil ifTrue:[
                    self drawThumb.
                    ^ self
                ].
                tH := thumbFrame height.
                tW := thumbFrame width.
                oldLeft := oldFrame left.
                oldRight := oldLeft + tW.

                thumbLeft := thumbFrame left.
                thumbRight := thumbLeft + tW.

                top := thumbFrame top.

                (oldRight >= width) ifTrue:[
                    "cannot copy - thumb was behind end"
                    self drawThumbBackgroundInX:oldLeft y:top
                                          width:(width - oldLeft" - 1") height:tH.
                    self drawThumb.
                    ^ self
                ].

                self catchExpose.
                self copyFrom:self x:oldLeft y:top
                                 toX:thumbLeft y:top
                               width:tW height:tH.

                oldLeft > thumbLeft ifTrue:[
                    delta := oldLeft - thumbLeft.
                    oldLeft > thumbRight ifTrue:[
                        self drawThumbBackgroundInX:oldLeft y:top
                                              width:(tW + 1) height:tH
                    ] ifFalse:[
                        self drawThumbBackgroundInX:thumbRight y:top
                                              width:delta height:tH
                    ]
                ] ifFalse:[
                    delta := thumbLeft - oldLeft.
                    oldRight < thumbLeft ifTrue:[
                        self drawThumbBackgroundInX:oldLeft y:top
                                              width:tW + 1 height:tH
                    ] ifFalse:[
                        self drawThumbBackgroundInX:oldLeft y:top 
                                              width:delta height:tH
                    ]
                ].
                self waitForExpose
            ]
        ]
    ]
!

scrollLeftAction:aBlock
    "ignored -
     but implemented, so that scroller can be used in place of a scrollbar"
!

scrollRightAction:aBlock
    "ignored -
     but implemented, so that scroller can be used in place of a scrollbar"
! !