I’ve been working with NSTextView, trying to make it suitable for outlining, and been running into a number of problems. There is a class, NSTextList, wish would seem from the documentation to create list formatting. However, in reality it does not such thing. So my first question is, is there a simple way to programatically add a list into a NSTextView, like clicking the list button on the ruler does? I’ve found a number of mailing list posts asking this question, but I have not yet found an answer.

Having failed so far to find a simple way to do this and have the NSTextView manage my lists, I’ve subclassed it and overridden keyDown to handle the backspace, enter, and tab keys. I’ve found a bizarre behavior, though, with inserting into the NSTextStorage this sequence: @”\t{bullet}\t”, where {bullet} is the unicode for a bullet, and setting the NSParagraphStyleAttribute with a NSTextList. I’m using code that amounts to essentially this:

self textStorage] beginEditing]; [[NSMutableAttributedString *text = [[NSMutableAttributedString alloc]initWithAttributedString:[self textStorage]];

ps = text attributesAtIndex:[self selectedRange].location-1 effectiveRange:&effectiveRange] objectForKey:[[NSParagraphStyleAttributeName]; ps = text attributesAtIndex:[self selectedRange].location-1 effectiveRange:&effectiveRange] objectForKey:[[NSParagraphStyleAttributeName]; if(ps == nil)ps = [NSParagraphStyle defaultParagraphStyle]; NSMutableParagraphStyle *mps = [ps mutableCopy]; NSTextList *listItem = [[NSTextList alloc] initWithMarkerFormat: @”{circle}” options:nil]; if([mps textLists] == nil) { [mps setTextLists:[NSArray arrayWithObject:listItem]]; } else { NSArray *newList = mps textLists] mutableCopy]; [newList addObject:newList]; [mps setTextLists:newList]; } [[NSMutableString *tabs = [@”\t” mutableCopy]; for(int i = 0; i < currentIndentation; i++) { [tabs appendString:@”\t”]; } [text appendAttributedString: [[NSAttributedString alloc] initWithString:[NSString stringWithFormat:@”%@%@\t”, tabs, [listItem markerForItemNumber:1]] attributes:[NSDictionary dictionaryWithObject:mps forKey:NSParagraphStyleAttributeName]]]; self textStorage] setAttributedString:text]; [[self textStorage] endEditing];

For some reason, the [[NSTextView seems to recognize it as a list, which some weird behavior, including crashes if the user tries to press return inside the list. It also adds an extra line every time the user presses enter. If I don’t add the NSTextList, it no longer shows this behavior.

I’ve been working on this problem for a while now, and am now pretty stuck. The documentation surrounding NSTextList is terrible, and there is no (AFAIK) documentation about how NSTextView handles lists. Thanks in advance for any help.