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From: dfc@Inference.Com (Deborah Catalano)
Newsgroups: comp.windows.x.motif
Subject: autoscrolling in Text widget - how?
Message-ID: <9010102336.AA03454@Quaestor.inference>
Date: 10 Oct 90 23:36:05 GMT
References: <590@synopsys.COM>
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Lines: 32


>The widget always displays
>the top n lines and NOT the bottom n lines.

We had the same problem and finally found the solution.  There is an
undocumented function: XmTextScroll(widget, num_lines) in Motif 1.0.
We count the number of carriage-returns and compare the count to the
number of rows in the text widget (obtained using XtGetValues).  
Here's a segment from our code:

XtSetArg(arg[0], XmNrows, &rows);
XtGetValues(text_widget, arg, 1);
...

if (ch == '\n') {
    bottom_line++;
    if (bottom_line > rows) {
        XmTextScroll(text_widget, 1);
    }
}

I read about this function in Doug Young's book, "The X Window System --
Programming and Applications with Xt -- OSF/Motif Edition"

Hope this helps!  

-----------------------------------------------------------------------------
Debbie Catalano
Inference Corporation
catalano@inference.com
213-322-5004 x194
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