"

 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.

"

PanelView subclass:#VerticalPanelView

!

VerticalPanelView comment:'

COPYRIGHT (c) 1989 by Claus Gittinger

	      All Rights Reserved

'!

!VerticalPanelView 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 which arranges its child-views in a vertical column.

    All real work is done in PanelView - except the layout computation is

    redefined here.

    The layout is controlled the instance variables: 

	horizontalLayout and verticalLayout

    in addition to horizontalSpace and verticalSpace.

    The vertical layout can be any of:

	#top            arrange elements at the top

	#topSpace       arrange elements at the top, start with spacing

	#bottom         arrange elements at the bottom

	#bottomSpace    arrange elements at the bottom, start with spacing

	#center         arrange elements in the center

	#spread         spread elements evenly

	#spreadSpace    spread elements evenly with spacing at ends

	#fit            like spread, but resize elements for tight packing

	#fitSpace       like fit, with spacing

    the horizontal layout can be:

	#left           place element at the left

	#leftSpace      place element at the left, offset by horizontalSpace

	#center         place it horizontally centered

	#right          place it at the right

	#rightSpace     place it at the right, offset by horizontalSpace

	#fit            resize elements horizontally to fit this panel

	#fitSpace       like fit, but add spacing

    The defaults is #center for both directions.

    The layout is changed by the messages #verticalLayout: and #horizontalLayout:.

    For backward compatibility (to times, where only vLayout existed), the simple

    #layout: does the same as #verticalLayout:. Do not use this old method.

    If none of these layout/space combinations is exactly what you need in

    your application, create a subclass, and redefine the setChildPositions method.

"

!

examples

"

    These examples demonstrate the effect of different layout

    settings.

    You should try more examples, combining spacing and different

    verticalLayout:/horizontalLayout: combinations.

    example: default layout (centered)

    example: top-layout

    example: top-layout; horizontal fit

    example: top-layout; horizontal fit with space

    example: topSpace-layout

    example: bottom-layout

    example: bottomSpace-layout

    example: spread-layout

    example: spreadSpace-layout

    example: fit-layout

    example: fitSpace-layout

    example: fully fitSpace

    example: from top, each at left:

    example: centered, right:

    example: a panel in a panel

! !

!VerticalPanelView methodsFor:'layout'!

setChildPositions

    "(re)compute position of every child"

    |ypos space sumOfHeights numChilds l hEach hInside|

    subViews isNil ifTrue:[^ self].

    space := verticalSpace.

    numChilds := subViews size.

    hInside := height - (margin * 2) + (borderWidth*2) - subViews last borderWidth.

    vLayout == #fitSpace ifTrue:[

	"

	 adjust childs extents and set origins.

	 Be careful to avoid accumulation of rounding errors

	"

	hEach := (hInside - (numChilds + 1 * space)) / numChilds.

	ypos := space + margin - borderWidth.

    ] ifFalse:[

	vLayout == #fit ifTrue:[

	    "

	     adjust childs extents and set origins.

	     Be careful to avoid accumulation of rounding errors

	    "

	    hEach := (hInside - (numChilds - 1 * space)) / numChilds.

	    ypos := margin - borderWidth.

	] ifFalse:[

	    "

	     compute net height needed

	    "

	    sumOfHeights := subViews inject:0 into:[:sumSoFar :child | sumSoFar + child heightIncludingBorder].

	    l := vLayout.

	    ((l == #center) and:[numChilds == 1]) ifTrue:[

		l := #spread

	    ].

	    (l == #spread and:[numChilds == 1]) ifTrue:[

		l := #spreadSpace

	    ].

	    "

	     compute position of topmost subview and space between them;

	     if they do hardly fit, leave no space between them 

	    "

	    (sumOfHeights >= (height - (margin * 2))) ifTrue:[

		"

		 if we  have not enough space for all the elements, 

		 fill them tight, and show what can be shown (at least)

		"

		ypos := 0.

		space := 0

	    ] ifFalse:[

		((l == #bottom) or:[l == #bottomSpace]) ifTrue:[

		    ypos := height - (space * (numChilds - 1)) - sumOfHeights.

	"

		    borderWidth == 0 ifTrue:[

			ypos := ypos + space 

		    ].

	"           

		    l == #bottomSpace ifTrue:[

			ypos >= space ifTrue:[

			    ypos := ypos - space

			]

		    ].

		    ypos < 0 ifTrue:[

			space := space min:(height - sumOfHeights) // (numChilds + 1).

			ypos := height - (space * numChilds) - sumOfHeights.

		    ]

		] ifFalse: [

		    (l == #spread) ifTrue:[

			space := (height - sumOfHeights) // (numChilds - 1).

			ypos := 0.

			(space == 0) ifTrue:[

			    ypos := (height - sumOfHeights) // 2

			]

		    ] ifFalse: [

		      (l == #spreadSpace) ifTrue:[

			space := (height - sumOfHeights) // (numChilds + 1).

			ypos := space.

			(space == 0) ifTrue:[

			    ypos := (height - sumOfHeights) // 2

			]

		      ] ifFalse: [

			((l == #top) or:[l == #topSpace]) ifTrue:[

			    space := space min:(height - sumOfHeights) // (numChilds + 1).

			    l == #topSpace ifTrue:[

				ypos := space.

			    ] ifFalse:[

				ypos := 0

			    ]

			] ifFalse:[

			    "center"

			    ypos := (height - (sumOfHeights

						 + ((numChilds - 1) * space))) // 2.

			    ypos < 0 ifTrue:[

				space := (height - sumOfHeights) // (numChilds + 1).

				ypos := (height - (sumOfHeights

					       + ((numChilds - 1) * space))) // 2.

			    ]

			]

		      ]

		    ]

		]

	    ].

	].

    ].

    "

     now set positions

    "

    subViews do:[:child |

	hLayout == #left ifTrue:[

	    xpos := 0

	] ifFalse:[

	    hLayout == #leftSpace ifTrue:[

		xpos := horizontalSpace

	    ] ifFalse:[

		hLayout == #right ifTrue:[

		] ifFalse:[

		    hLayout == #rightSpace ifTrue:[

		    ] ifFalse:[

			hLayout == #fitSpace ifTrue:[

			    xpos := horizontalSpace.