Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!cs.utexas.edu!ut-emx!ccwf.cc.utexas.edu!kish
From: kish@ccwf.cc.utexas.edu (Kishore Sarathy)
Newsgroups: comp.sys.mac.programmer
Subject: Question on List Mgr.
Message-ID: <50621@ut-emx.uucp>
Date: 16 Jun 91 19:28:45 GMT
Sender: news@ut-emx.uucp
Reply-To: kish@ccwf.cc.utexas.edu (Kishore Sarathy)
Distribution: usa
Organization: The University of Texas at Austin
Lines: 34
Originator: kish@flubber.cc.utexas.edu

I am in the process of writing an editor for a statistical program.
I am using the List Manager & there are a few problems I can't seem
to fix. I would appreciate any hints/suggestions from  the mac
programmers in this news group.

Problem 1 : Highlighting of selected cells.
------------------------------------------
The program is  written such that clicking on a column or row heading
selects all the cells in  that column or row. I do this by repeatedly 
calling LSetSelect. This works fine & all cells are properly 
highlighted. If I now click on one of these highlighted cells, the
List Manager should unselect & invert all the previously selections & 
select only the last cell I clicked on. Instead, the List mgr inverts 
only new cell I clicked on. It does not invert the the other unselected
cells ! It works fine if my mouse click was on an unselected cell.
The selection flag I use now is lNoDisjoint. 

Problem 2 : Selecting cells by pressing mouse & dragging.
--------------------------------------------------------
I want to be able to select cells ( in rectangles ) by pressing the 
mouse & dragging it. So I set the lExtendDrag flag also ( in addition
to lNoDisjoint). In this mode I cant seem to shrink selected cells by
moving the mouse in reverse i.e once the selection is made by dragging
the mouse, it can only be increased, not shrunk !

I am not very clear on how the List Mgr handles highlighting of 
selections ( especially the way LClick operates).

This is my first program on the mac & obviously I am missing something !       
The program is in Pascal & I am using Think Pascal 3.01. 

Thanks in advance !!

Kishore Sarathy.