how to download files from dropbox and show to user in iOS

Hello,
i need to show all files to user his dropbox account when user selects any file i need to download the file for that i have created a directory with name Dropbox as shown below.

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
dataPath = [documentsDirectory stringByAppendingPathComponent:@"/Dropbox"];

NSError *error;

if (![[NSFileManager defaultManager] fileExistsAtPath:dataPath])
  [[NSFileManager defaultManager] createDirectoryAtPath:dataPath withIntermediateDirectories:NO attributes:nil   error:&error];

self.restClient = [[DBRestClient alloc] initWithSession:[DBSession sharedSession]];
self.restClient.delegate = self;
[self.restClient loadMetadata:@"/"];

i was checking with metadata whether it is folder or file if folder i was loading file into my destination path as below.

- (void)restClient:(DBRestClient *)client loadedMetadata:(DBMetadata *)metadata {
    if (metadata.isDirectory) {
        NSLog(@"Folder '%@' contains:", metadata.path);
        for (DBMetadata *file in metadata.contents) {
            NSLog(@"file name%@", file.filename);
            if (file.isDirectory) {

                [self.restClient loadMetadata:[NSString stringWithFormat:@"/%@",file.filename]];

            }
           [self.restClient loadFile:file.path intoPath:dataPath];
        }
    }
}

when i tried to access the files in my directory there are no contents

NSString *extension = @"jpg";
NSFileManager *fileManager = [[NSFileManager alloc]init];

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *Kdatatype = [documentsDirectory stringByAppendingPathComponent:@"/Dropbox"];
NSArray *contents = [fileManager contentsOfDirectoryAtPath:Kdatatype error:nil];
NSMutableArray *jpegFiles = [NSMutableArray arrayWithCapacity: [contents count]];

NSString *filename;
for (filename in contents)        
{
    if ([[filename pathExtension] isEqualToString:extension])
    {
        [jpegFiles addObject:[UIImage imageNamed:[dataPath stringByAppendingPathComponent:filename]]];
    }
}

Query:
can any one help me out how to show user Dropbox files and download user selected file.