"

 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.

"

SimpleView subclass:#ScrollableView

       instanceVariableNames:'scrolledView scrollBar helpView innerMargin

			      scrollBarPosition lockUpdates'

       classVariableNames:'DefaultScrolledViewLevel'

       poolDictionaries:''

       category:'Views-Basic'

!

!ScrollableView class methodsFor:'documentation'!

copyright

"

 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.

"

!

version

!

documentation

"

    a view containing a scrollbar and some other (slave-)view.

    This view wraps scrollbar(s) around the view to be scrolled.

    The scrollbars are setup to send scrollUp/scrollDown/scrollVerticalTo

    and scrollLeft/scrollRight/scrollHorizontalTo- messages whenever moved.

    The view itself has to implement these (there is a default implementation

    in the common View class for this.

    For the scrollbars to know about the full (maximum) size, the view

    must implement #heightOfContents and/or #widthOfContents.

    The values returned by these methods are used to compute the fraction

    which is visible (i.e. the scrollers thumb heights).

    There are two ways to create a ScrollableView:

    if the type of the view to be scrolled is known in advance,

    use:

	v := ScrollableView for:<ViewClass>

    or:

	v := ScrollableView for:<ViewClass> in:someSuperView

    otherwise, create the scrollableView empty with:

	v := ScrollableView new

    or:

	v := ScrollableView in:someSuperView

    and define the view later with:

	v scrolledView:aViewToBeScrolled

    Finally, if the view to be scrolled has been already created,

    use:

	v := ScrollableView forView:aViewToBeScrolled

    or:    

	v := ScrollableView forView:aViewToBeScrolled in:someSuperView

    It is also possible to change the scrolledView later (even multiple times).

    This may be useful, if different views are needed to display different types

    of data (see example2) and at creation time, it is not known what type

    of view is required (multimedia applications).

    If you want to scroll views (instead of a views contents), you need a 

    companion class (ViewScroller). See the documentation there.

    If you need horizontal scrolling too, use an instance of HVScrollableView.

    By default, scrollbars are full size scrollbars - for horizontal scrolling

    (which is less often used), scrollableViews can optionally be created with

    miniscrollers which take up less screen space.

    TODO:

	this is pretty old and needs a rewrite. There are quite some

	historic leftovers found here and things can be done better

	(especially in initializeFor...)

	Also, it should be rewritten into one class which supports both

	Vertical-only, Horizontal-only and HV scrolling.

	Currently, horizontal-only scrolling is not available.

	(you have to write your own class ...)

	Finally, some means to hide scrollbars should be added - this would

	give more screenspace to the view when all is visible 

	(and therefore, the scrollbars are not needed, anyway)

	Expect the above things to be fixed in an upcoming version.

"

!

examples

"

    example1 (simple scrolled text):

	|top scr txt|

	top := StandardSystemView label:'scroll example1'.

	top extent:200@100.

	scr := ScrollableView for:EditTextView in:top.

	scr origin:0.0@0.0 corner:1.0@1.0.

	txt := scr scrolledView.

	txt list:#('line1'

		   'line2'

		   'line3'

		   'line4'

		   'line5'

		   'line7'

		   'line8'

		   'line9'

		   'line10'

		  ).

	top open

    example2 (changing the scrolledView later):

	|top scr txtView1 txtView2 browserView|

	top := StandardSystemView label:'scroll example2'.

	top extent:300@100.

	scr := ScrollableView in:top.

	scr origin:0.0@0.0 corner:1.0@1.0.

	top open.

	(Delay forSeconds:5) wait.

	txtView1 := EditTextView new.

	txtView1 list:#(

			'wait 5 seconds to see the other text'

			'line2'

			'line3'

			'line4'

			'line5'

			'line7'

			'line8'

			'line9'

			'line10'

		  ).

	scr scrolledView:txtView1.

	(Delay forSeconds:5) wait.

	txtView2 := EditTextView new.

	txtView2 list:#('this is the other views text' 

			'alternative line2'

			'alternative line3'

			'alternative line4'

			'alternative line5'

			'alternative line6').

	scr scrolledView:txtView2.

    example3 (using a miniscroller):

	|top scr txt|

	top := StandardSystemView label:'scroll example3'.

	top extent:200@100.

	scr := ScrollableView for:EditTextView miniScroller:true in:top.

	scr origin:0.0@0.0 corner:1.0@1.0.

	txt := scr scrolledView.

	txt list:#('line1'

		   'line2'

		   'line3'

		   'line4'

		   'line5'

		   'line7'

		   'line8'

		   'line9'

		   'line10'

		  ).

	top open

    example4 (scrolling in both directions):

	|top scr txt|

	top := StandardSystemView label:'scroll example4'.

	top extent:200@100.

	scr := HVScrollableView for:EditTextView in:top.

	scr origin:0.0@0.0 corner:1.0@1.0.

	txt := scr scrolledView.

	txt list:#('line1'

		   'line2'

		   'line3'

		   'line4'

		   'line5'

		   'line7'

		   'line8'

		   'line9'

		   'line10'

		  ).

	top open

    example5 (using a full scroller vertically, miniscroller horizontally):

	|top scr txt|

	top := StandardSystemView label:'scroll example5'.

	top extent:200@100.

	scr := HVScrollableView for:EditTextView miniScrollerH:true in:top.

	scr origin:0.0@0.0 corner:1.0@1.0.

	txt := scr scrolledView.

	txt list:#('line1'

		   'line2'

		   'line3'

		   'line4'

		   'line5'

		   'line7'

		   'line8'

		   'line9'

		   'line10'

		  ).

	top open

    example6 (using miniscrollers for both directions ):

	|top scr txt|

	top := StandardSystemView label:'scroll example6'.

	top extent:200@100.

	scr := HVScrollableView for:EditTextView miniScroller:true in:top.

	scr origin:0.0@0.0 corner:1.0@1.0.

	txt := scr scrolledView.

	txt list:#('line1'

		   'line2'

		   'line3'

		   'line4'

		   'line5'

		   'line7'

		   'line8'

		   'line9'

		   'line10'

		  ).

	top open

"

! !

!ScrollableView class methodsFor:'defaults'!

updateStyleCache

    |d|

    StyleSheet name == #st80 ifTrue:[

	d := 1

    ] ifFalse:[

	StyleSheet is3D ifTrue:[

	    d := -1

	] ifFalse:[

	    d := 0

	]

    ].

    DefaultScrolledViewLevel := StyleSheet at:'scrolledViewLevel' default:d.

    "Modified: 31.8.1995 / 04:05:55 / claus"

! !

!ScrollableView class methodsFor:'instance creation'!

miniScroller:mini

    "return a new scrolling view. The subview will be created later.

     The view will have full scrollbars if mini is false, 

     miniscrollers if true."

    ^ self for:nil miniScrollerH:mini miniScrollerV:mini 

!

miniScrollerH:miniH

    "return a new scrolling view. The subview will be created later.

     The view will have full scrollbars if miniH is false, 

     and a horizontal miniscroller if true."

    ^ self for:nil miniScrollerH:miniH miniScrollerV:false in:nil

!

miniScrollerH:miniH miniScrollerV:miniV

    "return a new scrolling view. The subview will be created later.

     The view will have full scrollbars if the corresponding miniH/miniV

     is false, miniscrollers if true."

    ^ self for:nil miniScrollerH:miniH miniScrollerV:miniV in:nil

!

in:aView

    "return a new scrolling view to be contained in aView.

     There is no slave view now - this has to be set later via

     the scrolledView: method.

     The view will have full scrollbars."

    ^ self for:nil miniScrollerH:false miniScrollerV:false in:aView

!

forView:aView

    "return a new scrolling view scrolling aView.

     The view will have full scrollbars."

    ^ self forView:aView miniScrollerH:false miniScrollerV:false in:nil

!

forView:scrolledView miniScrollerH:miniH miniScrollerV:miniV in:aView

    "return a new scrolling view, scrolling aView.

     The view will have full scrollbars if the corresponding miniH/miniV

     is false, miniscrollers if true."

    |newView|

    newView := self for:nil miniScrollerH:miniH miniScrollerV:miniV in:aView.

    newView scrolledView:scrolledView.

    ^ newView

!

for:aViewClass

    "return a new scrolling view scrolling an instance of aViewClass.

     The subview is created here.

     The view will have full scrollbars."

    ^ self for:aViewClass miniScrollerH:false miniScrollerV:false in:nil

!

for:aViewClass in:aView

    "return a new scrolling view scrolling an instance of aViewClass.

     The subview is created here.

     The view will have full scrollbars."

    ^ self for:aViewClass miniScrollerH:false miniScrollerV:false in:aView

!

for:aViewClass miniScrollerH:miniH

    "return a new scrolling view scrolling an instance of aViewClass.

     The subview is created here.

     The view will have full scrollbars if miniH is false, 

     and a horizontal miniscroller if true."

    ^ self for:aViewClass miniScrollerH:miniH miniScrollerV:false in:nil

!

for:aViewClass miniScrollerH:miniH miniScrollerV:miniV

    "return a new scrolling view scrolling an instance of aViewClass.

     The subview is created here.

     The view will have full scrollbars if the corresponding miniH/miniV

     is false, miniscrollers if true."

    ^ self for:aViewClass miniScrollerH:miniH miniScrollerV:miniV in:nil

!

for:aViewClass miniScroller:mini

    "return a new scrolling view scrolling an instance of aViewClass.

     The subview is created here.

     The view will have full scrollbars if mini is false, miniscrollers

     if true."

    ^ self for:aViewClass miniScrollerH:mini miniScrollerV:mini in:nil 

!

for:aViewClass miniScroller:mini in:aView

    "return a new scrolling view scrolling an instance of aViewClass.

     The subview is created here.

     The view will have full scrollbars if mini is false, miniscrollers

     if true."

    ^ self for:aViewClass miniScrollerH:mini miniScrollerV:mini in:aView 

!

for:aViewClass miniScrollerH:miniH in:aView

    "return a new scrolling view scrolling an instance of aViewClass.

     The subview is created here.

     The view will have full scrollbars if miniH is false, 

     and a horizontal miniscroller if true."

    ^ self for:aViewClass miniScrollerH:miniH miniScrollerV:false in:aView 

!

for:aViewClass miniScrollerH:miniH miniScrollerV:miniV in:aView

    "return a new scrolling view scrolling an instance of aViewClass.

     The subview is created here.

     The view will have full scrollbars if the corresponding miniH/miniV

     is false, miniscrollers if true."

    |newView|

    aView notNil ifTrue:[

	newView := self basicNew.

	newView device:(aView device).

	aView addSubView:newView

    ] ifFalse:[

	"create on Display by default"

	newView := self basicNew device:Display.

    ].

    newView initializeFor:aViewClass miniScrollerH:miniH miniScrollerV:miniV.

    ^ newView

! !

!ScrollableView methodsFor:'initialization'!

initialize

    "default setup: full scrollers"

    ^ self initializeFor:nil miniScrollerH:false miniScrollerV:false 

!

initializeFor:aViewClass miniScrollerH:miniH miniScrollerV:miniV 

    |negativeOffset twoMargins halfMargin cls isST80 isOpenWin is3D lvl extra|

    super initialize.

    lockUpdates := false.

    "

     mhmh - these must go into the stylesheet as well...

    "

    isST80 := styleSheet name = #st80.

    isOpenWin := styleSheet name = #openwin.

    isOpenWin ifTrue:[self level:0].

    is3D := styleSheet is3D.

    isST80 ifTrue:[

	innerMargin := 0

    ] ifFalse:[

	is3D ifTrue:[

	    innerMargin := ViewSpacing.

	] ifFalse:[

	    innerMargin := 0    

	]

    ].

    negativeOffset := borderWidth negated.

    "create the scrollbar"

    isST80 ifTrue:[

	cls := ScrollBar

    ] ifFalse:[

	cls := miniV ifTrue:[MiniScroller] ifFalse:[ScrollBar].

    ].

    scrollBar := cls in:self.

    scrollBar thumbOrigin:0 thumbHeight:100.

    extra := 0.

    "create the subview"

    is3D ifTrue:[

	twoMargins := innerMargin * 2.

	halfMargin := innerMargin // 2.

	aViewClass notNil ifTrue:[