NSMatrix woes

[Christopher Culver]

The latest difficulty in my Charmap application relates to the 
NSMatrix class. Charmap is organised in such a way that clicking on 
an NSBrowser entry (representing a Unicode block, e.g. Greek 
Extended, CJK Unified Ideographs, etc) calls a Controller method 
that redraws the charmap. That is, the Controller removes all cells, 
adds only the number of cells necessary for that Unicode block, and 
fills the cells each with one character.

Here's how I remove the cells:
 // Remove all cells
 int numRows = [charmapMatrix numberOfRows];
 int numColumns = [charmapMatrix numberOfColumns];
 for (i = numRows; i > 0; i--)
   [charmapMatrix removeRow: i];
 for (j = numColumns; j > 0; j--)
   [charmapMatrix removeColumn: j];

This works just fine, and if that's all there is to it then the 
result is an empty NSMatrix. However, the problem lies in adding new 
rows and columns. This is an oversimplification, but this is what 
I'm doing that doesn't work:
  //  Add the necessary cells
 [charmapMatrix addRow];
 [charmapMatrix addRow];
 [charmapMatrix addColumn];
 [charmapMatrix addColumn];

Though this should result in two columns and two rows, i.e. four 
cells, it doesn't. No matter how many times I call addRow and 
addColumn, in the end the NSMatrix displays only one row and one 
column, i.e. one cell.

I have been sure to call  [charmapMatrix setNeedsDisplay: YES] 
before this method returns, but it doesn't make a difference. So, 
what am I doing wrong with this NSMatrix? How do I add rows and 
cells in a way that actually works?

If anyone wants to see the code, you can checkout charmap from 
Savannah. The current CVS commit has the problem which I'm asking 
about here. Be aware the application doesn't actually do anything 
yet.

Christopher Culver