Expanding SMXMLDocument

Just a quick post here due to time constraints.

I don’t have time to submit this properly through GitHub because I haven’t cloned the repo, but I did want to share it since finding and using this class saved me a few hours of effort.

This is a small extension to SMXMLDocument (a very useful iOS XML parser, thanks, Nick) which will return all children for a given path (specified as an array of strings), not just the first match it finds.

- (NSArray *)descendantsWithPath:(NSArray *)path {
  NSMutableArray *lineage = [NSMutableArray arrayWithArray:path];
  NSMutableArray *array = [NSMutableArray array];

  NSArray *kids = [self childrenNamed:[lineage objectAtIndex:0]];
  [lineage removeObjectAtIndex:0];

  if ([kids count] > 0) {
    if (0 == [lineage count]) {
      // bottom of path
      [array addObjectsFromArray:kids];
    } else {
      // recurse into path
      for (SMXMLElement *el in kids) {
        NSArray *elements = [el descendantsWithPath:lineage];

        if ([elements count] > 0)
          [array addObjectsFromArray:elements];
      }
    }
  }
  return array;
}

This can be easily extended to:

- (NSArray *)descendantsWithPath:(NSArray *)path andAttribute:(NSString *)attribute

To find only leaf nodes on the given path with a specific attribute, but I haven’t gotten that far in my own project yet–possibly a future update to this post.

Note: This was based on the master-arc branch supporting ARC.

Enjoy!