iphone - DocumentDirectory の ImagePath を NSURL Iphone に変換する

Question

次のコードを使用しています

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES);
NSURL *myUrl = [[NSURL alloc] initWithString:self.selectedRing.ringThumbNailImagePath];
[Utilities responseDataFromURL:myUrl completionBlock:^(NSData *fileData, NSError *err)
{
    if (err != nil)
    {
        [self.indicator stopAnimating];
        [Utilities errorDisplay:@""];
    }
    else
    {
        NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"Test.igo"];
        NSLog(@"FilePath: %@", filePath);

        if ([fileData writeToFile:filePath atomically:YES])
        {
            CGRect rect = CGRectMake(0 ,0 , 0, 0);    
            NSURL *igImageHookFile = [[NSURL alloc] initWithString:[[NSString alloc] initWithFormat:@"file://%@", filePath]];
            NSLog(@"JPG path %@", filePath);

ファイルパスは

Users/umar/Library/Application Support/iPhone Simulator/6.1/Applications/B45223CF-B437-4617-A02D-DCA91C965A5A/Documents/Test.igo

ただし、Nil igImageHookFile NSURL を取得します。なにが問題ですか？