disabling radiobutton in Cocoa

I have 2 radio buttons ( NSMatrix with 2 rows and 1 column) and have defined them in the 开发者_如何学JAVAheader file as IBOutlet NSMatrix *temp;

Now when I pick a certain option, I want to disable both these radio button's or at times I want to disable the radiobutton in row 1. Any tips on how I can do this ? I can't seem to find the delgates to do this.

Thanks.

// Disable top
[[temp cellAtRow:0 column:0] setEnabled:NO];

// Disable bottom
[[temp cellAtRow:1 column:0] setEnabled:NO];

// Disable both
[temp setEnabled:NO];