macOS SearchKit CoreService found nothing - xcode

Question

im working on an that search in the content of allot of files, i planed to use SearchKit but i can't figure out to make Apple's sample code to work, and i can't find any other ressources (NSHipster code didn't work either), here's my code:
#define kSearchMax 1000
#interface ViewController()
#property(nonatomic) SKIndexRef mySKIndex;
#end
#implementation ViewController
#synthesize mySKIndex;
- (void)viewDidLoad {
[super viewDidLoad];
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^{
[self openIndex];
[self addDoc];
SKIndexFlush(self.mySKIndex);
// i thought that the indexation may need some time ..
sleep(2);
dispatch_async(dispatch_get_main_queue(), ^{
[self searchterm:#"var"];
});
});
}
- (void) openIndex {
NSString *path = [[NSHomeDirectory() stringByAppendingPathComponent:#"index"] stringByAppendingPathExtension:#"txt"]; // 1
NSURL *url = [NSURL fileURLWithPath:path];
NSString *name = #"extension_index";
if ([name length] == 0) name = nil;
SKIndexType type = kSKIndexInverted;
if ([[NSFileManager defaultManager] fileExistsAtPath:path]) {
mySKIndex = SKIndexOpenWithURL ((__bridge CFURLRef) url,
(__bridge CFStringRef) name,
true
);
}else{
self.mySKIndex = SKIndexCreateWithURL((__bridge CFURLRef) url,
(__bridge CFStringRef) name,
(SKIndexType) type,
(CFDictionaryRef) NULL);
}
}
- (void) addDoc {
SKLoadDefaultExtractorPlugIns ();
NSString *path = [NSBundle.mainBundle pathForResource:#"Products" ofType:#"rtf"]; // 1
NSURL *url = [NSURL fileURLWithPath: path]; // 2
SKDocumentRef doc = SKDocumentCreateWithURL ((__bridge CFURLRef) url);
NSString *mimeTypeHint = #"text/rtf";
BOOL added = SKIndexAddDocument ((SKIndexRef) mySKIndex,
(SKDocumentRef) doc,
(__bridge CFStringRef)mimeTypeHint,
(Boolean) true
);
NSLog(added ? #"added" : #"not added");
}
- (void) searchterm:(NSString*)query{
SKSearchOptions options = kSKSearchOptionDefault;
BOOL more = YES;
UInt32 totalCount = 0;
SKSearchRef search = SKSearchCreate (mySKIndex,
(__bridge CFStringRef) query,
options);
while (more) {
SKDocumentID foundDocIDs [kSearchMax];
float foundScores [kSearchMax];
float *scores;
Boolean unranked =
options & kSKSearchOptionNoRelevanceScores;
if (unranked) {
scores = NULL;
} else {
scores = foundScores;
}
CFIndex foundCount = 0;
more = SKSearchFindMatches (
search,
kSearchMax,
foundDocIDs,
scores,
100,
&foundCount
);
NSLog(#"%#", [NSString stringWithFormat:#"current count = %i", totalCount]);
totalCount += foundCount;
}
}
#end
it always print "current count = 0" and the loop is executed only one time.