Prevent Preview of Custom UTI File Types on iPad

Question

I have an iPad application with a custom file type declared via UTI and CFBundleDocumentTypes. Is there a way I can prevent applications like Mail and Dropbox from showing the file Preview while still allowing the "Open In..." option to launch my app? I have set UITypeConformsTo and UTTypeTagSpecification to custom values in the application Info-plist, but the other apps are still previewing files with the custom extension created by my app. I thought the ability to preview was dependent on the value in the UTTypeTagSpecification (i.e. mime-type), but apparently not. Thanks.

Answer 1

The only solution I have found is to compress the file (e.g. ZIP). This will prevent iPad apps from displaying the contents. You do still need to be careful when declaring your custom doc types. Otherwise the app may still try to preview even though it's compressed, and end up displaying gibberish.