Image Grabbing with iOS Share Extension

Question

how can I check that the app or page has an image to be grabbed, and grab it to use later from an iOS Share Extension using SWIFT?

Answer 1

You are thinking about this backwards, iOS will do that for you. All you can/have to do is define what you accept, see and keep in mind that by default all documents you accept have to be present at once or the share won't show up NSExtensionActivationRule

Answer 2

you can determine this using the ExtensionPreprocessingJS, in the run function

run: function(arguments) {
   arguments.completionFunction({"numberImages" : document.images.length});
 }