Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!mips!sgi!shinobu!fido.wpd.sgi.com!marktwain.rad.sgi.com!linton
From: linton@marktwain.rad.sgi.com (Mark Linton)
Newsgroups: comp.windows.interviews
Subject: Re: Viewports and scrolling .....
Message-ID: <1991May7.183844.22317@fido.wpd.sgi.com>
Date: 7 May 91 18:38:44 GMT
References: <9105061618.AA04456@ntlp.com>
Sender: news@fido.wpd.sgi.com (Usenet News Admin)
Reply-To: linton@marktwain.rad.sgi.com (Mark Linton)
Organization: sgi
Lines: 74

In article <9105061618.AA04456@ntlp.com>, lolita!david@UUNET.UU.NET writes:
|> 
|> 	
|> 	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.

Trays don't constrain the size of their components, so putting the box in the tray
doesn't help.  What you want is a Viewport or MonoScene subclass with a specific
shape.  3.0 provides FixedSpan for glyphs; you want the analogous interactor.
Below is your test case with a Shaper class that does what you want (I think).

#include <InterViews/box.h>
#include <InterViews/frame.h>
#include <InterViews/glue.h>
#include <InterViews/message.h>
#include <InterViews/scrollbar.h>
#include <InterViews/viewport.h>
#include <InterViews/world.h>

class Shaper : public MonoScene {
public:
    Shaper(Interactor*, Shape&);
protected:
    virtual void Reconfig();
};

Shaper::Shaper(Interactor* i, Shape& s) {
    *shape = s;
    Insert(i);
}

void Shaper::Reconfig() {
    /* don't copy child's shape */
}

int main(int argc, char** argv) {
    World w("Test", argc, argv);

    VBox* listBox = new VBox;
    listBox->Insert(new Message("The first one"));
    listBox->Insert(new Message("The second one"));
    listBox->Insert(new Message("The third one"));
    listBox->Insert(new Message("The fourth one"));
    listBox->Insert(new Message("The fifth one"));
    listBox->Insert(new Message("The sixth one"));
    listBox->Insert(new Message("The seventh one"));
    listBox->Insert(new Message("The eighth one"));
    listBox->Insert(new Message("The last one"));

    Viewport* theViewer = new Viewport(listBox, TopLeft);
    Shape s;
    s.Rect(round(2.5*inches), round(.5*inches));
    w.Insert(
	new HBox(
	    new Shaper(theViewer, s),
	    new VScrollBar(theViewer)
	)
    );
    w.run();
}