將從Cloudkit提取的數據從一個視圖控制器傳遞到另一個視圖控制器

Question

我有一個調用此函數並調用performSegueWithIdentifier的按鈕。 Segue發生在數據是兩個查詢返回數據之前。我該如何解決這個問題？

-(void)recommendSomeone { 
    NSString *currentUserID = [NSString stringWithFormat:@"%@%@",@"KU",self.liaResponse[@"id"]]; 
    CKContainer *myContainer = [CKContainer defaultContainer]; 
    CKDatabase *publicDatabase = [myContainer publicCloudDatabase]; 
    CKRecordID *currentUserRecordID = [[CKRecordID alloc] initWithRecordName:currentUserID]; 
    CKReference *recordToMatch = [[CKReference alloc] initWithRecordID:currentUserRecordID action:CKReferenceActionNone]; 

    NSPredicate *predicate = [NSPredicate predicateWithFormat:@"contactList CONTAINS %@",recordToMatch]; 
CKQuery *query = [[CKQuery alloc] initWithRecordType:@"knotworkGhostUsers" predicate:predicate]; 
[publicDatabase performQuery:query inZoneWithID:nil completionHandler:^(NSArray *results, NSError *error) { 
    if (error) { 
     // Error handling for failed fetch from public database 
     NSLog(@"error querying knotwork users %@", error); 
    } 
    else { 
     // Display the fetched records 
     self.randomGhostUser = results[arc4random_uniform([results count])]; 
     NSLog(@"this is the first name %@", self.randomGhostUser[@"firstname"]); 
     NSLog(@"knotwork ghost users for current user data returned ordinary title %@",results); 
     NSString* searchQuery = @" "; 
     NSString *kuTitle = [self.randomGhostUser[@"title"] lowercaseString]; 
     NSArray *keyWords = @[@"developer",@"networking",@"sales manager",@"engineer",@"doctor",@"facility manager"]; 
     for(NSString* keyWord in keyWords){ 
      NSRange checkResult = [kuTitle rangeOfString:keyWord]; 
      if(checkResult.location != NSNotFound){ 
       searchQuery = [NSString stringWithFormat:@"%@%@%@",searchQuery,@" ",keyWord]; 
      } 
     } 

     NSPredicate *predicate = [NSPredicate predicateWithFormat:@"allTokens tokenmatches[cdl] %@ AND contactList CONTAINS %@",searchQuery,recordToMatch]; 
     CKQuery *query2 = [[CKQuery alloc] initWithRecordType:@"knotworkGhostUsers" predicate:predicate]; 
     [publicDatabase performQuery:query2 inZoneWithID:nil completionHandler:^(NSArray *response, NSError *error) { 
      if (error) { 
       // Error handling for failed fetch from public database 
       NSLog(@"error querying knotwork users %@", error); 
      } 
      else { 
       // Display the fetched records 
       self.recommendedGhostUser = response; 
       NSLog(@"knotwork users data returned after recom %@", self.recommendedGhostUser); 
      } 
     }]; 
    } 
    [self performSegueWithIdentifier:@"Recommend" sender:nil]; 

}]; 

} 強調文本

Answer 1

您必須更換賽格瑞並把它放在你的第二個完成區塊內。 因爲否則您的完成塊將在您已經推入了segue之後調用。你

[publicDatabase performQuery:query2 inZoneWithID:nil completionHandler:^(NSArray *response, NSError *error) { 
      if (error) { 
       // Error handling for failed fetch from public database 
       NSLog(@"error querying knotwork users %@", error); 
      } 
      else { 
       // Display the fetched records 
       self.recommendedGhostUser = response; 
       NSLog(@"knotwork users data returned after recom %@", self.recommendedGhostUser); 
       //Put it in here 
       [self performSegueWithIdentifier:@"Recommend" sender:nil]; 
      } 
     }]; 

也可以使用prepareForSegue您的值傳遞給第二控制器：

- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender 
{ 
    // Set Segue name from storyboard 
    if ([[segue identifier] isEqualToString:@"seguename"]) 
    { 
     // Get reference to the destination view controller 
     YourViewController *vc = [segue destinationViewController]; 

     // Pass any objects to the view controller here, like... 
     [vc setMyObjectHere:object]; 
    } 
} 

（Link to segue-answer）