"

 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.

"

"{ Package: 'stx:libwidg' }"

SimpleView subclass:#ScrollableView

	instanceVariableNames:'scrolledView vScrollBar hScrollBar scrollBarPosition lockUpdates

		hideVScrollBar hideHScrollBar hasHorizontalScrollBar

		hasVerticalScrollBar horizontalMini verticalMini vScrollBarHidden

		hScrollBarHidden scrolledViewHMargin scrolledViewVMargin

		scrollBarVSpacing scrollBarHSpacing scrolledViewLayout

		hScrollBarLayout vScrollBarLayout'

	classVariableNames:'DefaultScrolledViewLevel DefaultScrolledViewMargin

		DefaultScrollBarSpacing DefaultScrolledViewBorderWidth

		DefaultLevel DefaultScrollBarLevel MyDefaultViewBackgroundColor'

	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.

"

!

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 - so your widgets usually dont have to

    care for this).

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

    MUST implement #heightOfContents and/or #widthOfContents.

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

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

    There are three ways to setup 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 an empty scrollableView 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 (multidocument format applications).

    If you want to scroll a bucnh of other 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.

    Recent changes:

        Originally, there where two classes, for vertical-only and

        horizontal+vertical scrollability.

        These have now been merged into the common ScrollableView class,

        and each scrollability can be controlled individually.

        The original HVScrollableView class is almost empty, but remains

        for backward compatibility (it simply initializes the scrollability

        flags for H+V scrollability).

    [author:]

        Claus Gittinger

    [see also:]

        ScrollBar Scroller

         HVScrollableView

"

!

examples

"

  simple scrolled text:

                                                                        [exBegin]

        |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

                                                                        [exEnd]

  changing the scrolledView later:

                                                                        [exBegin]

        |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.

                                                                        [exEnd]

  using a miniscroller:

                                                                        [exBegin]

        |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

                                                                        [exEnd]

  scrolling in both directions:

    Notice: HVScrollableView remains existent for backward compatibility;

            scrollability can now be controlled in both directions at any

            time (see examples below).

                                                                        [exBegin]

        |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

                                                                        [exEnd]

  using a full scroller vertically, miniscroller horizontally:

    Notice: HVScrollableView remains existent for backward compatibility;

            scrollability can now be controlled in both directions at any

            time (see examples below).

                                                                        [exBegin]

        |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

                                                                        [exEnd]

  using miniscrollers for both directions:

    Notice: HVScrollableView remains existent for backward compatibility;

            scrollability can now be controlled in both directions at any

            time (see examples below).

                                                                        [exBegin]

        |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

                                                                        [exEnd]

  controlling scrollability:

                                                                        [exBegin]

        |top scr txt|

        top := StandardSystemView label:'scroll example6'.

        top extent:200@100.

        txt := EditTextView new.

        scr := ScrollableView forView:txt in:top.

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

        scr horizontalScrollable:true.

        scr verticalScrollable:false.

        txt list:#('line1'

                   'line2'

                   'line3'

                   'line4'

                   'line5'

                   'line7'

                   'line8'

                   'line9'

                   'line10'

                  ).

        top open

                                                                        [exEnd]

  controlling scrollability and miniScroller:

                                                                        [exBegin]

        |top scr txt|

        top := StandardSystemView label:'scroll example6'.

        top extent:200@100.

        txt := EditTextView new.

        scr := ScrollableView forView:txt in:top.

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

        scr horizontalScrollable:true; horizontalMini:false.

        scr verticalScrollable:true; verticalMini:true.

        txt list:#('line1'

                   'line2'

                   'line3'

                   'line4'

                   'line5'

                   'line7'

                   'line8'

                   'line9'

                   'line10'

                  ).

        top open

                                                                        [exEnd]

  autohiding scrollbars (edit the text to make scrollbars visible/invisible)

  (NOTICE:

        this is controlled by the styleSheet and 

        should normally NOT be done by the program):

                                                                        [exBegin]

        |top scr txt|

        top := StandardSystemView label:'scroll example6'.

        top extent:200@100.

        txt := EditTextView new.

        scr := ScrollableView forView:txt in:top.

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

        scr horizontalScrollable:true; horizontalMini:false.

        scr verticalScrollable:true; verticalMini:true.

        scr autoHideScrollBars:true.

        txt list:#('line1'

                   'line2'

                   'line3'

                   'line4'

                   'line5'

                   'line7'

                   'line8'

                   'line9'

                   'line10'

                  ).

        top open

                                                                        [exEnd]

"

! !

!ScrollableView class methodsFor:'instance creation'!

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

        hasHorizontalScrollBar:self defaultHorizontalScrollable

        hasVerticalScrollBar:self defaultVerticalScrollable

        miniScrollerH:false 

        miniScrollerV:false 

        origin:nil

        corner:nil 

        in:nil

    "Created: 6.3.1997 / 18:06:22 / cg"

    "Modified: 6.3.1997 / 23:18:32 / cg"

!

for:aViewClass hasHorizontalScrollBar:hasH hasVerticalScrollBar:hasV 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."

    |newView|

    aViewClass notNil ifTrue:[

        newView := aViewClass new.

    ].

    ^ self

        forView:newView

        hasHorizontalScrollBar:hasH 

        hasVerticalScrollBar:hasV 

        miniScrollerH:miniH 

        miniScrollerV:miniV 

        origin:nil 

        corner:nil 

        in:nil

    "Created: 7.4.1997 / 19:00:14 / cg"

!

for:aViewClass hasHorizontalScrollBar:hasH hasVerticalScrollBar:hasV miniScrollerH:miniH miniScrollerV:miniV origin:org corner:corn 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|

    aViewClass notNil ifTrue:[

        newView := aViewClass new.

    ].

    ^ self

        forView:newView

        hasHorizontalScrollBar:hasH 

        hasVerticalScrollBar:hasV 

        miniScrollerH:miniH 

        miniScrollerV:miniV 

        origin:org 

        corner:corn 

        in:aView

    "

     |top scr|

     top := StandardSystemView extent:200@200.

     scr := ScrollableView for:nil

                 hasHorizontalScrollBar:true

                 hasVerticalScrollBar:true

                 miniScrollerH:false

                 miniScrollerV:false

                 origin:0.0@0.0

                 corner:1.0@1.0

                 in:top.

     top open

    "

    "Modified: 6.3.1997 / 18:36:01 / cg"

!

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

        hasHorizontalScrollBar:self defaultHorizontalScrollable