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From: lolita!david@UUNET.UU.NET
Newsgroups: comp.windows.interviews
Subject: Viewports and scrolling .....
Message-ID: <9105061618.AA04456@ntlp.com>
Date: 6 May 91 16:18:32 GMT
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	This is an InterViews 2.6 question.

	O.K. I give up.  What I want to be able to do is to insert an arbitrary
Interactor into something that will allow me to view a specified (smaller)
portion of said interactor.  I would also like to be ablt to attach ScrollBars
to this thing.  I would expect the ScrollBars to configure themselves so that
I can view all of the interactor.  I had thought I was going to be able get this
behaviour out of a Viewport, but on futher inspection realized that there wasn't
a way to specify the "initial size" of the viewport; it defaults to the size of
the inserted interactor.   Then I stumbled onto Trays and thought aha! this will
do it, only to find out that the scrollbar refused to behave.  Below is an
example of the Tray/Viewport version.  The only problem with this is that the
ScrollBar thinks (reasonably) that there's no more resizing to be done. 
Actually I can move around a bit by using the Up/Down Movers.  This doesn't work
well, nor in a particularlly inteligent way, so I gotta believe I'm just not
doing the right thing.

	Any help would be apreciated.  


	.
	.
	.

	// Something to scroll around.
	VBox *listBox = new VBox;
	listBox->Insert( Message( "The first one"));
	listBox->Insert( Message( "The second one"));
		.
		.
		.
	listBox->Insert( Message( "The n'th one"));

        // Use a viewport here to give something for the scrollbar to talk to.
	Viewport *theViewer = new Viewport( listBox, TopLeft);

	// Make a tray with a background the "right size" and 
	// stick theViewer into it.
	VBox *theSize = new VBox( 
		new VGlue( (Coord)round( .5*inches), 0, 0),
		new HBox( new HGlue( (Coord)round( 2.5*inches, 0, 0)
	);
	Tray *aTray = new Tray( theSize);
	aTray->Aligh( TopLeft, theViewer);

	// Build a Frame suitable for putting into the world
	// with the above and include a scrollbar for theViewer.
	MarginFrame *whatWeSee = new MarginFrame(
		new HBox(
			aTray,
			new VScrollBar( theViewer)
		),
		(Coord) round( .5*inches)
	);
	.
	.
	.


	Thanks alot,


	David


Daivd Rivas						david@lolita.ntlp.com
Northfield Trading L. P.				(303) 985-3366