Preview of dropbox file in iOS

Question

I am integrating dropbox with my IOS application. I am able to fetch selected file meta data. But couldn't find the way to show preview after selecting the file. Can someone suggest which API is helpful.

Drop box i am using is : https://www.dropbox.com/developers/dropins/chooser/ios

Below piece of code is called when user wants to select file from dropbox :

- (void)didPressChoose
{   
    [[DBChooser defaultChooser] openChooserForLinkType:DBChooserLinkTypePreview fromViewController:self
                                            completion:^(NSArray *results)
     {   
         if ([results count]) {
             _result = results[0];
             //After getting the result, i want to preview the file
         } else {
             _result = nil;
             [[[UIAlertView alloc] initWithTitle:@"CANCELLED" message:@"user cancelled!"
                                        delegate:nil cancelButtonTitle:@"Okay" otherButtonTitles:nil]
              show];
         }
         [[self tableView] reloadData];
     }];
}

Answer 1

When you ask for DBChooserLinkTypePreview, the DBChooserResult you get back from the Chooser will have an NSURL link like this:

https://www.dropbox.com/s/toyzur6e0m34t7v/dropbox-logos_dropbox-glyph-blue.png

This link type is meant for direct user interaction, so you can send a user there and Dropbox will display the page with a preview of the file if possible.

Alternatively, you may want to use DBChooserLinkTypeDirect which gives you a direct link like this:

https://dl.dropboxusercontent.com/1/view/969vkzdys770277/Testing/Images/dropbox-logos_dropbox-glyph-blue.png

This is a direct (but temporary) link to the file contents. You can download the file contents programmatically (e.g., see How do I download and save a file locally on iOS using objective C? ) and then do whatever you want with it. For example, you may want to display it in an UIImageView if it's an image, etc.

Also, DBChooserResult contains a thumbnails property with links to thumbnails (if the selected file was an image or video) that might be similarly useful.