在Parse.com中使用指针User进行查询

Question

我在我的应用程序中使用Parse.com,我创建了一个"Post"类,在里面我有一个指针指定哪个用户发送了帖子.现在我在帖子的时间轴上看到了创建帖子的用户名的时间.由于用户是指针,我无法进行正确的查询,您知道如何解决此问题吗？

Answer 1

诀窍是使用PFQuery includeKeyParse自动填充相关指针数据.该user数据将不要求你做另一个查询它下载.

PFQuery *query = [PFQuery queryWithClassName:@"Post"];

// Include the user data with each post
[query includeKey:@"title_of_userpointer_column"];

[query findObjectsInBackgroundWithBlock:^(NSArray *postObjects, NSError *error)
 {
     if (!error) {
         NSLog(@"Successfully retrieved: %d items", [postObjects count]);

         // postObjects now contains the latest 100 Posts, and the "title_of_userpointer_column" field
         // has been populated.
         // For example:
         for (PFObject * postObject in postObjects) {

             // This does not require a network access.
             PFObject *postAuthor = [postObject objectForKey:@"title_of_userpointer_column"];
             NSLog(@"retrieved related Post Author: %@", postAuthor);
         }
 }