I’ve seen many ways to implement delete in an NSTableView. Many are good. Many hardcode references to something they shouldn’t, and those are bad.

Here’s an easy way:

Subclass NSTableView and override keyDown:

- (void)keyDown:(NSEvent *)theEvent {
    // handle delete
    unichar key = [[theEvent charactersIgnoringModifiers] characterAtIndex:0];
    if (key == NSDeleteCharacter && self.selectedRow != -1) {
        [NSApp sendAction:@selector(delete:) to:nil from:self];
    } else {
      [super keyDown:theEvent];
  }
}

This just lets the responder chain take care of it. Your window controller can easily handle it by just implementing delete:

- (IBAction)delete:(id)sender {
    if (self.tableView.selectedRowIndexes.count > 0) {
        [_tableView beginUpdates];
        [[self _patternSequence] removeChildrenAtIndexes:self.tableView.selectedRowIndexes];
        [_tableView endUpdates];
    }
}

EDIT: I probably should only call super keyDown if it wasn’t the delete key…otherwise we beep.

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