How to have a share extension to show up for multiple photos

I'm having difficulty to have my share extension to show up in the list of extensions when multiple photos or urls are selected in photos, dropbox, etc

switched NSExtensionActivationRule from dict to a string per apple documentation:

   <key>NSExtension</key>
        <dict>
                <key>NSExtensionAttributes</key>
                <dict>
                        <key>NSExtensionActivationRule</key>
                        <string>{extensionItems = ({
    attachments = ({
        registeredTypeIdentifiers = (
            "public.url", "public.file-url", "public.image"
        );
    });
})}</string>
                </dict>
                <key>NSExtensionMainStoryboard</key>
                <string>MainInterface</string>
                <key>NSExtensionPointIdentifier</key>
                <string>com.apple.share-services</string>
        </dict>

Now the extension does not get listed even for a single image let alone for a set. How to I fix this?

Solution

NSExtensionActivationRule as dictionary works fine. The issues was not plist itself but xcode. Somehow the change from 1 to 256 was not picked up.

This is not an ios issue. This seems to be an xcode[8.2.1] dependencies issue.