DeletableTableView, an NSTableView subclass which supports delete.

DeletableTableView.h

#import <Cocoa/Cocoa.h>

@interface DeletableTableView : NSTableView {
}
@end

@protocol DeletableTableViewDelegate
- (void)tableViewDelete:(DeletableTableView *)aView;
@end

DeletableTableView.m

#import "DeletableTableView.h"

@implementation DeletableTableView

- (IBAction)delete:(id)sender {
	if ([self numberOfSelectedRows] > 0) 
		[[self delegate] tableViewDelete:self];
}

- (void)deleteBackward:(id)sender {
	[self delete:nil];
}

- (void)deleteForward:(id)sender {
	[self delete:nil];
}

- (void)keyDown:(NSEvent *)event {
	NSString* chars = [event charactersIgnoringModifiers];
	if ([chars length] == 1) {
		unichar c = [chars characterAtIndex:0];
		if (c == NSDeleteCharacter || c == NSDeleteFunctionKey) {
			[self delete:nil];
		}
	}
	
}	

- (BOOL)validateUserInterfaceItem:(id <NSValidatedUserInterfaceItem>)anItem {
	BOOL result = NO;
	
	if ([anItem action] == @selector(delete:)) {
		result = ([self numberOfSelectedRows] > 0);
	} else {
		result = [super validateUserInterfaceItem:anItem];
	}
	return result;
}

@end