GUI.SetTopLinePart of GUI module

Syntax   GUI.SetTopLine (widgetID : int, lineNum : int)

Description   The GUI.SetTopLine procedure scrolls the text in a text box so as to place the line number specified by lineNum at the top of the text box (if possible). This is often used to scroll the text back to the beginning of the text box by assigning a value of 1 to lineNum.
Example   This program displays 100 lines of text in a text box, then sets the text box to display line 50 at the top of the box.

        import GUI

        var textBox : int     % The Text Field ID.
        textBox := GUI.CreateTextBoxFull (10, 10, 180, 275,
            GUI.INDENT, 0)

        GUI.SetBackgroundColor (gray)

        % Read the file and place it in the text box.
        for i : 1 .. 100
            GUI.AddLine (textBox, intstr (i))
        end for
        GUI.SetTopLine (textBox, 50)

        loop
            exit when GUI.ProcessEvent
        end loop
Execute  

Status   Exported qualified.

This means that you can only call the function by calling GUI.SetTopLine, not by calling SetTopLine.