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problem with SCROLLPOS in Rich Edit

Hi,
I'm using a rich edit control to make a word processor.
In my code I do the following
            POINT scrollPos;
            m_MyRichEditControl.SendMessage(EM_GETSCROLLPOS, 0, reinterpret_cast<LPARAM>(&scrollPos));

       //
//operations to change some content of the edit control
//

            m_MyRichEditControl.SendMessage(EM_SETSCROLLPOS, 0, reinterpret_cast<LPARAM>(&scrollPos));

As a result I find the document has scrolled to a different position. And no, I havent changed the value of scrollPos.
Any reason why this happens?

AndyAinscow

A guess - is it positioning the scroll pos to the center or top of the visible area? (Do you really require the EM_SETSCROLLPOS message?)

DanRollins

What sort of edit operation did you do? I can concieve of some that would make the original value invalid and thus make the control appear to behave oddly when you reused it.

ashugarg00

ASKER

The edit operations are not causing it to change. I did a EM_GETSCROLLPOS and immediately after that did a EM_SETSCROLLPOS, found the scrollPos valu had changed even without any edit operations.

DanRollins

The API documentation indicates that the RTF control *will* adjust the value in some cases. It says the following:

Rich Edit checks the X and Y coordinates and adjusts them if necessary, so
that a complete line is displayed at the top. It also ensures that the text is
never completely scrolled off the view rectangle.

Is that what is happening to you?

ashugarg00

ASKER

I got the solution to my problem. The problem was in the range of the scroll pos which is 2 bytes i.e 65535. However our file was huge which required a scroll pos beyond the above range.

DanRollins

Recommend: Refund / Save in the PAQ

AndyAinscow

I concur

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