如果UIImage沒有從網址加載

Question

如果圖像不從url加載，我如何將本地image.png添加到單元格？

- (UITableViewCell*)tableView:(UITableView*)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{ 
    static NSString *CellIdentifier = @"Cell"; 
    DetailCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier]; 

    NSURL* url = [NSURL URLWithString:[arrayOfImages objectAtIndex:indexPath.row]]; 
    NSURLRequest* request = [NSURLRequest requestWithURL:url]; 
    [NSURLConnection sendAsynchronousRequest:request 
             queue:[NSOperationQueue mainQueue] 
          completionHandler:^(NSURLResponse * response, 
               NSData * imagedata, 
               NSError * error) { 
           if (!error){ 
            UIImage* image = [[UIImage alloc] initWithData:imagedata]; 
            cell.flowerImage.image = image; 
           }      
    }]; 

    return cell; 
} 

arrayOfImages - 我從json解析過的url字符串數組。

Answer 1

您可以通過檢查圖像來檢查圖像的URL。

[NSURLConnection sendAsynchronousRequest:request 
            queue:[NSOperationQueue mainQueue] 
         completionHandler:^(NSURLResponse * response, 
              NSData * imagedata, 
              NSError * error) { 
          if (!error){ 
           UIImage* image = [[UIImage alloc] initWithData:imagedata]; 
           if(!image) { 
            cell.flowerImage.image = [UIImage imageNamed:@"localImage"]; //local bundle image. 
           } else 
            cell.flowerImage.image = image; 
          } else { 
           cell.flowerImage.image = [UIImage imageNamed:@"localImage"];//local bundle image. 
          } 
}];