如何从parse.com检索图像

Question

嗨,我是新手使用parse.com实际上我试图在parse.com中保存图像并重新审视它..但我成功保存图像为 PFFile

在parse.com仪表板中它显示如下

现在我如何在UIImageView中检索图像和显示

我试过这样但是它不起作用..

 PFQuery *query = [PFQuery queryWithClassName:@"UserPhoto"];
    [query whereKey:@"userName" containsString:@"ravi"];
    [query getObjectInBackgroundWithId:@"ID" block:^(PFObject *object, NSError *error) {
        if(!error){
            PFFile *im = [object objectForKey:@"imageFile"];
            _getImg.image = im;
        }}];

在这里,我想要回顾特定的形象 userName ravi

Answer 1

要检索图像,您需要:

1. 查询有PFObject问题的人
2. 使用-[PFFile getDataInBackgroundWithBlock:]检索PFFile的数据

3. UIImage用结果创建一个NSData

   PFQuery *query = [PFQuery queryWithClassName:@"UserPhoto"];
   
   [query whereKey:@"userName" containsString:@"ravi"];
   
   [query getFirstObjectInBackgroundWithBlock:^(PFObject *object, NSError *error) {
       if (!object) {
           return NSLog(@"%@", error);
       }
   
       PFFile *imageFile = object[@"imageFile"];
   
       [imageFile getDataInBackgroundWithBlock:^(NSData *data, NSError *error) {
           if (!data) {
               return NSLog(@"%@", error);
           }
   
           // Do something with the image
           self.imageView.image = [UIImage imageWithData:data];
       }];
   }];
   

顺便说一句,除非纯粹用于实验,或者你正在执行主线程的某些操作,否则我会避免PFObject同步使用-[PFObject save]和使用异步版本-[PFObject saveInBackgroundWithBlock:].