Go to your project.
Select the application’s landing page and open the "Information" tab.
Now in the "Document Types" add a document type with these settings:
Name: "whatever" or "image" Types: public.image
Save this and compile the application. Your application should now appear in an open ... list from other applications.
Now run apple. Open supported file types and continue development.
For a complete list of types, follow these steps: Uniform description of type identifiers
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