"

 COPYRIGHT (c) 1999 by eXept Software AG

              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.

"

ListModelView subclass:#SelectionInListModelView

	instanceVariableNames:'selection multipleSelectOk actionBlock doubleClickActionBlock

		selectConditionBlock clickLine highlightMode useIndex

		ignoreReselect toggleSelect hilightFgColor hilightBgColor

		hilightLevel hilightFrameColor hilightStyle dragAccessPoint

		dropTarget dropSource'

	classVariableNames:'DefaultHilightStyle DefaultHilightBackgroundColor

		DefaultHilightForegroundColor DefaultHilightLevel

		DefaultHilightFrameColor'

	poolDictionaries:''

	category:'Views-Lists'

!

!SelectionInListModelView class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1999 by eXept Software AG

              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

"

    SelectionInListModelView is mostly like SelectionInListView,

    but derives from the ListModelView and thus the list is kept

    by the model.

    [Instance variables:]

        selection               <misc>     the current selection. nil, a number or collection of numbers

        multipleSelectOk        <Boolean>  allow/disallow multiple selections( default:false )

        actionBlock             <Block>    action evaluated on single click

        doubleClickActionBlock  <Block>    action evaluated on double click

        clickPosition           <Point>    internal use

        highlightMode           <Symbol>   how to draw the selection

        useIndex                <Boolean>  representation of the model selection

        ignoreReselect          <Boolean>  if set, a click on an already selected entry is ignored

        toggleSelect            <Boolean>  a click on an entry unselects it and vice versa

        hilightFgColor          <Color>    foregroundColor of highlighted items       

        hilightBgColor          <Color>    backgroundColor of highlighted items

        hilightLevel            <Integer>  level to draw selections (i.e. for 3D effect)

        hilightFrameColor       <Color>    rectangle around highlighted items

        hilightStyle            <Boolean>  actions on widget are enabled/disabled

    [author:]

        Claus Atzkern

    [see also:]

        ListModelView

        HierarchicalListView

"

!

examples

"

                                                                        [exBegin]

    |top list view|

    list := List new.

    1 to:100 do:[:i| list add:('element: ', i printString) ].

    top  := StandardSystemView new; extent:300@300.

    view := ScrollableView for:SelectionInListModelView miniScroller:true

                        origin:0.0@0.0 corner:1.0@1.0 in:top.

    view list:list.

    top  open.

                                                                        [exEnd]

                                                                        [exBegin]

    |top list view item|

    list := HierarchicalList new.

    item := HierarchicalItem::Example labeled:'Test'.

    item expand.

    list showRoot:false.

    list root:item.

    top  := StandardSystemView new; extent:300@300.

    view := ScrollableView for:SelectionInListModelView miniScroller:true

                        origin:0.0@0.0 corner:1.0@1.0 in:top.

    view list:list.

    view doubleClickAction:[:i| (list at:i) toggleExpand ].

    top  open.

                                                                        [exEnd]

"

! !

!SelectionInListModelView class methodsFor:'defaults'!

updateStyleCache

    "extract values from the styleSheet and cache them in class variables"

    <resource: #style   (

                        #'selection.hilightForegroundColor' #'selection.hilightBackgroundColor'

                        #'selection.hilightFrameColor'      #'selection.hilightLevel'

                        #'selection.foregroundColor'        #'selection.backgroundColor'

                        #'selection.shadowColor'            #'selection.lightColor'

                        #'selection.font'                   #'selection.hilightStyle'

                        #'text.foregroundColor'

                        )>

    DefaultHilightForegroundColor  := StyleSheet colorAt:'selection.hilightForegroundColor'.

    DefaultHilightBackgroundColor  := StyleSheet colorAt:'selection.hilightBackgroundColor'.

    DefaultHilightFrameColor       := StyleSheet colorAt:'selection.hilightFrameColor'.

    DefaultHilightLevel            := StyleSheet at:'selection.hilightLevel' default:0.

    DefaultHilightStyle            := StyleSheet at:'selection.hilightStyle' default:(StyleSheet name).

    DefaultForegroundColor         := StyleSheet colorAt:'selection.foregroundColor'.

    DefaultBackgroundColor         := StyleSheet colorAt:'selection.backgroundColor'.

    DefaultShadowColor             := StyleSheet colorAt:'selection.shadowColor'.

    DefaultLightColor              := StyleSheet colorAt:'selection.lightColor'.

    DefaultForegroundColor isNil ifTrue:[

        DefaultForegroundColor := StyleSheet colorAt:'text.foregroundColor' default:Black

    ].

    "

     self updateStyleCache

    "

! !

!SelectionInListModelView methodsFor:'accessing'!

list:aList

    "get the status of <showRoot> from the list

    "

    self deselectWithoutRedraw.

  ^ super list:aList

! !

!SelectionInListModelView methodsFor:'accessing actions'!

action

    "get the action block to be performed on select

    "

    ^ actionBlock

!

action:aOneArgAction

    "set the action block to be performed on select

    "

    actionBlock := aOneArgAction

!

doubleClickAction

    "get the action block to be performed on doubleclick

    "

    ^ doubleClickActionBlock

!

doubleClickAction:aOneArgAction

    "set the action block to be performed on doubleclick

    "

    doubleClickActionBlock := aOneArgAction

!

selectConditionBlock

    "set the conditionBlock; this block is evaluated before a selection

     change is performed; the change will not be done, if the evaluation

     returns false

    "

    ^ selectConditionBlock

!

selectConditionBlock:aOneArgBlock

    "set the conditionBlock; this block is evaluated before a selection

     change is performed; the change will not be done, if the evaluation

     returns false

    "

    selectConditionBlock := aOneArgBlock.

! !

!SelectionInListModelView methodsFor:'accessing behavior'!

highlightMode

    "get the mode how to draw a selected line:

        #line           draw whole line selected

        #label          draw label selected

    "

    ^ highlightMode

!

highlightMode:aMode

    "set the mode how to draw a selected line:

        #line           draw whole line selected

        #label          draw label selected

    "

    highlightMode := aMode.

!

ignoreReselect

    "get the ignoreReselect flag - see method #ignoreReselect: for more details

    "

    ^ ignoreReselect

!

ignoreReselect:aBoolean

    "set/clear the ignoreReselect flag - 

     if set, a click on an already selected entry is ignored.

     Otherwise the notification is done, even if no

     change in the selection occurs.

     (for example, in browser to update a method).

     Setting ignoreReselect to false makes sense if data is shown

     which may change by itself (i.e. without the user doing anything)

     For example, the inspector uses this, and redisplays the value,

     if the selection is the same.

     The default is true, meaning that a click on an already selected

     does not lead to a notification via the actionBlock/change mechanism.

    "

    ignoreReselect := aBoolean

!

multipleSelectOk

    "allow/disallow multiple selections; the default is false

    "

    ^ multipleSelectOk

!

multipleSelectOk:aState

    "allow/disallow multiple selections; the default is false

    "

    multipleSelectOk := aState ? false.

!

toggleSelect

    "get the toggleSelect flag - see method #toggleSelect: for more details

    "

    ^ toggleSelect

!

toggleSelect:aBoolean

    "turn on/off toggle select. If true, clicking on a selected entry

     unselects it and vice versa. The default is false, which means

     that clicking on an already selected entry does not change its

     select status (see also ignoreReselect:).

    "

    toggleSelect := aBoolean.

!

useIndex

    "set/clear the useIndex flag.

     the selection writen to the model are the indices into the list

     or the elements selected.

    "

    ^ useIndex

!

useIndex:aBoolean

    "set/clear the useIndex flag.

     the selection writen to the model are the indices into the list

     or the elements selected.

    "

    useIndex := aBoolean ? true

! !

!SelectionInListModelView methodsFor:'change & update'!

argForChangeMessage

    "return the argument for a selectionChange;

     depending on the setting of useIndex, this is either the numeric

     index of the selection or the value (i.e. the string)

    "

    selection isNil ifTrue:[

        multipleSelectOk ifTrue:[^ #()].

        ^ useIndex ifTrue:[0] ifFalse:[nil]

    ].

    useIndex ifTrue:[^ selection].

    multipleSelectOk ifFalse:[

        ^ list at:selection ifAbsent:nil

    ].

    ^ selection collect:[:nr| list at:nr ifAbsent:nil ]

!

listSizeChanged:aLnNr nLines:aDeltaLines

    "update selection

    "

    |changed cnts|

    super listSizeChanged:aLnNr nLines:aDeltaLines.

    selection isNil ifTrue:[^ self].

    list size == 0 ifTrue:[

        selection := nil.

      ^ self selectionChanged

    ].

    multipleSelectOk ifFalse:[

        selection < aLnNr ifTrue:[^ self].

        selection := selection + aDeltaLines.

        (aDeltaLines < 0 and:[selection < aLnNr]) ifTrue:[

            selection := nil.

          ^ self selectionChanged

        ]

    ] ifTrue:[

        changed := false.

        aDeltaLines < 0  ifFalse:[

            selection keysAndValuesDo:[:i :ln|

                ln >= aLnNr ifTrue:[

                    changed := true.

                    selection at:i put:(ln + aDeltaLines)

                ]

            ]

        ] ifTrue:[

            cnts := 0.

            selection keysAndValuesDo:[:i :ln||new|

                ln >= aLnNr ifTrue:[

                    changed := true.

                    (new := ln + aDeltaLines) < aLnNr ifTrue:[

                        cnts := cnts + 1.

                        new  := nil

                    ].

                    selection at:i put:new

                ]

            ].

            cnts ~~ 0 ifTrue:[

                cnts == selection size ifTrue:[

                    selection := nil

                ] ifFalse:[

                    selection := selection select:[:ln| ln notNil]

                ].

              ^ self selectionChanged.

            ].

        ].

        changed ifFalse:[^ self].

    ].

    (useIndex and:[model notNil]) ifTrue:[

        model setValue:(self argForChangeMessage)

    ].

!

selectionChanged

    "selection has changed. Call actionblock and/or send changeMessage if defined

    "

    |arg|

    (model isNil and:[actionBlock isNil]) ifTrue:[

        ^ self

    ].

    arg := self argForChangeMessage.

    model notNil ifTrue:[

        model removeDependent:self.

        "/ change models value to force a change notification: reselect mode

        model setValue:(arg isNil ifTrue:[0] ifFalse:[nil]).

        self sendChangeMessage:#value: with:arg.

        model addDependent:self.

    ].

    actionBlock notNil ifTrue:[

        (actionBlock numArgs) == 1 ifTrue:[

            actionBlock value:arg

        ] ifFalse:[

            actionBlock value

        ]

    ].

!

update:something with:aParameter from:changedObject

    "check wether my model changed

    "

    |newSelection|

    changedObject == model ifTrue:[

        self syncPushEvent:#updateFromModel

    ] ifFalse:[

        super update:something with:aParameter from:changedObject

    ].

!

updateFromModel

    "update selection from the model

    "

    model isNil ifTrue:[

        ^ self

    ].

    self syncFlushEvent:#updateFromModel.

    value := model value.

    (useIndex or:[value isNil or:[value isNumber]]) ifFalse:[

        multipleSelectOk ifFalse:[

            value := list identityIndexOf:value

        ] ifTrue:[

            value isEmpty ifTrue:[

                value := nil

            ] ifFalse:[

                nsel := OrderedCollection new.

                value do:[:e||i|(i := list identityIndexOf:e) ~~ 0 ifTrue:[nsel add:i]].

                value := nsel notEmpty ifTrue:[nsel] ifFalse:[nil]

            ]

        ].

    ].

    self setSelection:value.

! !

!SelectionInListModelView methodsFor:'drag & drop'!

canDrag

    "returns true if dragging is enabled

    "

    ^ dropSource notNil

!

dropSource

    "returns the dropSource or nil

    "

    ^ dropSource

!

dropSource:aDropSourceOrNil

    "set the dropSource or nil

    "

    dropSource := aDropSourceOrNil.

!

dropTarget

    "returns the dropTarget or nil

    "

    ^ dropTarget

!

dropTarget:aDropTragetOrNil

    "set the dropTarget or nil

    "

    dropTarget := aDropTragetOrNil.

!

startDragAt:aPoint

    "start drag at a point

    "