data disappear out of UNIUrlConnection - ios

Question

What I'm trying to do is to pass data from my Objective-C to my swift file.
Recently, when I have successfully connected my objective c file with my swift file, I can print data that get from UNIUrlConnection(which means the connection between swift and objective-c works fine).
Then I create a NSMutableDictionary object and add those data into NSMutableDictionary. I want to pass this NSMutableDictionary object to my swift file so that I can output them on my viewController.
However, the NSMutableDictionary contains correct data within the UNIUrlConnection but then contains none out of UNIUrlConnection. Thus the NSMutableDictionary passed to swift file would always contain no data. How can I solve this?
This is my objective c file.
#import <Foundation/Foundation.h>
#import <UNIRest.h>
#import "findByIngredients.h"
#implementation findByIngredients
-(NSMutableDictionary*) connectAPI:(NSString*) ingredients Number:(NSString*) number{
NSMutableDictionary *temp = [NSMutableDictionary dictionaryWithCapacity:10];
NSString* url = #"https://spoonacular-recipe-food-nutrition-v1.p.mashape.com/recipes/findByIngredients?fillIngredients=false";
if (![ingredients isEqual: #""]) {
NSString* ingre = #"&ingredients=";
ingre = [ingre stringByAppendingString:ingredients];
url = [url stringByAppendingString:ingre];
}
else {
NSString* ingre = #"&ingredients=<required>";
url = [url stringByAppendingString:ingre];
}
NSString* LL = #"&limitLicense=false";
url = [url stringByAppendingString:LL];
if (![number isEqual: #""]) {
NSString* numberOfReturn = #"&number=";
numberOfReturn = [numberOfReturn stringByAppendingString:number];
url = [url stringByAppendingString:numberOfReturn];
}
NSString* ranking = #"&ranking=1";
url = [url stringByAppendingString:ranking];
// These code snippets use an open-source library. http://unirest.io/objective-c
NSDictionary *headers = #{#"X-Mashape-Key": #"KEY", #"Accept": #"application/json"};
UNIUrlConnection *asyncConnection = [[UNIRest get:^(UNISimpleRequest *request) {
[request setUrl:url];
[request setHeaders:headers];
}] asJsonAsync:^(UNIHTTPJsonResponse *response, NSError *error) {
NSInteger code = response.code;
NSDictionary *responseHeaders = response.headers;
UNIJsonNode *body = response.body;
NSData *rawBody = response.rawBody;
if (rawBody) {
id allKeys = [NSJSONSerialization JSONObjectWithData:rawBody options:0 error:&error];
for (int i=0; i<[allKeys count]; i++) {
NSDictionary *arrayResult = [allKeys objectAtIndex:i];
// NSString* myNewString = [NSString stringWithFormat:#"%d", i];
NSString *key = [arrayResult objectForKey:#"id"];
NSString *value = [arrayResult objectForKey:#"title"];
[temp setObject:value forKey:key];
NSLog(#"id=%#",[arrayResult objectForKey:#"id"]);
NSLog(#"title=%#",[arrayResult objectForKey:#"title"]);
}
}
int size = [temp count];
NSLog(#"temp size is %d",size);
NSLog(#"successfully test API");
}];
// int size = [temp count];
// NSLog(#"temp size is %d",size);
return temp;
}
#end
Here the size of temp within UNIUrlConnection is correct. But if I put the size before return (which I comment out), it shows 0, which is wrong.
This is my swift file.
#IBAction func search(_ sender: Any) {
let ingreArr = IngredientsText.text.components(separatedBy: [",", " "])
var ingre:String = ingreArr[0]
let sep:String = "%2C"
for (index,element) in ingreArr.enumerated() {
if (index >= 1) {
ingre = ingre + sep + element
}
}
let test = findByIngredients()
// test.connectAPI(ingre, number: NumberOfResults.text)
let result: Dictionary = test.connectAPI(ingre, number: NumberOfResults.text) as Dictionary
let num:Int = result.count
print(num)
}
The num is 0.