给定模型对象，如何在NSTreeController中找到索引路径？ [英] Given model object, how to find index path in NSTreeController?

问题描述

给定 NSTreeController 的模型对象，如何在树中找到它们的索引路径，然后选择它们？这似乎是一个明显的问题，但我似乎没有找到任何参考。任何想法？

解决方案

没有简单的方式，你必须走树节点并找到一个匹配的索引路径例如：

Objective-C：

类别

  @implementation NSTreeController（附加）
 
  - （NSIndexPath *）indexPathOfObject： 
 {
 return [self indexPathOfObject：anObject inNodes：[[self arrangedObjects] childNodes]]; 
} 
 
  - （NSIndexPath *）indexPathOfObject：（id）anObject inNodes：（NSArray *）nodes 
 {
 for（NSTreeNode * nodes in nodes）
 {
 if（[[node referencedObject] isEqual：anObject]）
 return [node indexPath]; 
 if（[[node childNodes] count]）
 {
 NSIndexPath * path = [self indexPathOfObject：anObject inNodes：[node childNodes]]; 
 if（path）
返回路径; 
} 
} 
 return nil; 
} 
 @end 
  

Swift： / p>

扩展

 扩展NSTreeController {
 
 func indexPathOfObject（anObject：NSObject） - > NSIndexPath？ {
 return self.indexPathOfObject（anObject，nodes：self.arrangedObjects.childNodes）
} 
 
 func indexPathOfObject（anObject：NSObject，nodes：[NSTreeNode]！） - > NSIndexPath？ {
 for node in nodes {
 if（anObject == node.representedObject as！NSObject）{
 return node.indexPath 
} 
 if（node.childNodes！ = nil）{
 if let path：NSIndexPath = self.indexPathOfObject（anObject，nodes：node.childNodes）
 {
返回路径
} 
} 
} 
 return nil 
} 
} 
  

Given model objects that NSTreeController represents, how do you find their index paths in the tree and subsequently select them? This seems to be a blindingly obvious problem, but I can't seem to find any reference to it. Any ideas?

解决方案

There's no "easy" way, you have to walk the tree nodes and find a matching index path, something like:

Objective-C:

Category

@implementation NSTreeController (Additions)

- (NSIndexPath*)indexPathOfObject:(id)anObject
{
    return [self indexPathOfObject:anObject inNodes:[[self arrangedObjects] childNodes]];
}

- (NSIndexPath*)indexPathOfObject:(id)anObject inNodes:(NSArray*)nodes
{
    for(NSTreeNode* node in nodes)
    {
        if([[node representedObject] isEqual:anObject])
            return [node indexPath];
        if([[node childNodes] count])
        {
            NSIndexPath* path = [self indexPathOfObject:anObject inNodes:[node childNodes]];
            if(path)
                return path;
        }
    }
    return nil; 
}
@end    

Swift:

Extension

extension NSTreeController {

    func indexPathOfObject(anObject:NSObject) -> NSIndexPath? {
         return self.indexPathOfObject(anObject, nodes: self.arrangedObjects.childNodes)
    }

    func indexPathOfObject(anObject:NSObject, nodes:[NSTreeNode]!) -> NSIndexPath? {
         for node in nodes {
            if (anObject == node.representedObject as! NSObject)  {
                 return node.indexPath
            }
            if (node.childNodes != nil) {
                if let path:NSIndexPath = self.indexPathOfObject(anObject, nodes: node.childNodes)
                {
                     return path
                }
            }
        }
        return nil
    }
}

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