{ import: Scroll }
{ import: Frame }
{ include "SDL/SDL.h" }

"Quick hack"
PluggableDraggingHandler : DraggingHandler (motionBlock)
PluggableDraggingHandler motionBlock: aBlock [ motionBlock := aBlock ]
PluggableDraggingHandler motion	:anEvent
[
    motionBlock value: anEvent value: anEvent position - reference. box damaged
]

[
    | window yBar box pane1 pane2 image frame |
    window := Window new: 1000, 800.

    pane1 := ScrollPane new.
    window add: pane1.

    image := ImageBox newImage: (SDLImage fromBMP: 'alto.bmp').
    pane1 add: image.
    pane1 position: 30, 30.

    image buttonDown:
	((PluggableDraggingHandler with: image)
	     motionBlock: [:anEvent :position | pane1 scroll: position]).

    yBar := VScrollBar new.
    yBar extent: 20, pane1 height.
    yBar position: pane1 position + (pane1 width + 30, 0).
    yBar model inner: (30 size: 10) outer: (30 size: 420).
    window add: yBar.

    box := Box new.
    box background: ColorRed.
    box extent: 20, 20.
    window addFront: box.

    yBar model when: #changed do: [ :adj | box damaged; position: box position x, adj value; damaged ].
    box buttonDown:
	((PluggableDraggingHandler with: box)
	     motionBlock: [:anEvent :position |
		 box damaged.
		 box position: position.
		 yBar model value: position y.
		 box damaged]).

    pane2 := ScrollPane new.
    frame := FrameBox with: pane2 title: 'Picture'.
    image := ImageBox newImage: (SDLImage fromBMP: 'alto.bmp').
    pane2 add: image.

    image buttonDown:
	((PluggableDraggingHandler with: image)
	     motionBlock: [:anEvent :position | pane2 scroll: position]).

    window add: frame.
    frame position: pane1 position x, (pane1 position y + pane1 extent y + 30).

    window mainLoop.
]