NSTreeController add:method not adding "after the current selection"

3
votes

I have an NSTreeController bound to an NSOutlineView (no core data). From Cocoa's reference:

add:
Adds an object to the receiver after the current selection.
- (void)add:(id)sender

What's tripping me out is that when the add method is invoked it places the new item at the end of the list, NOT after the selected item. The insert method seems to work as expected (item added before the selection). Am I doing something wrong? How does one insert a new node after the selected item and not at the end of the list?

2
objective-ccocoa
Maybe it's something I'm doing wrong, but it seems NSTreeController and NSTreeNodes seems to be really buggy to the point of unsuitability. I've tried going the route of getting the parent node (which is the root in this case) and creating an NSMutableArray through mutableChildNodes:, which I then add a node to that array. When I do that I get an exception "-[NSTreeNode _setupObserving]: unrecognized selector sent to instance 0x20004f640 ", which to me means that NSTreeNode is not KVO compliant, even though the docs states that they are. – Gobot
You set up which keys are used in KVO for NSTreeController in Interface Builder, this sounds more like an issue with your bindings, not a bug. – LearnCocos2D

2 Answers

1
votes

What you probably want to do is call insertObject:atArrangedObjectIndexPath:.

Create an IBAction (i.e.: (IBAction)addAfterSelection:(id)sender) and have it instanciate your object, figure the selection's indexPath then call insertObject:atArrangedObjectIndexPath:.

If not that, perhaps verify ensure sorting happens on the NSOutlineView.

1
votes

Here's what I eventually ended up doing, I implemented a Category of NSIndexPath which calculates the next index path, and used that to insert a node. Here is the Category:

@implementation NSIndexPath (additions)
(NSIndexPath *)nextIndexPath:(NSIndexPath *)startingIndexPath
{
    NSUInteger pathIndexesArray[[startingIndexPath length]];
    [startingIndexPath getIndexes:pathIndexesArray];
    pathIndexesArray[[startingIndexPath length] - 1]++;
    return [NSIndexPath indexPathWithIndexes:pathIndexesArray length:[startingIndexPath length]];
}
@end