UIActivityViewController ignores third-party sharing extensions included in excludedActivityTypes

Number:rdar://19430419 Date Originated:1/9/2014
Status:Closed Resolved:Duplicate of #18989552
Product:iOS Product Version:iOS 8.1.2 (12B440)
Classification:Other Bug Reproducible:Yes
UIActivityViewController does not respect third-party activity types that are included in the excludedActivityTypes property.  For example, I may want to block users from sharing via a specific extension (i.e., Tumblr) for a valid reason (i.e., I am the Tumblr app and it doesn't make sense for me to share to myself) or I want to prevent a user from sharing potentially his or her private data with a social network but allow him or her to share to a productivity app like Dropbox or Evernote.

Steps to Reproduce:
1. Download the Tumblr app for iOS to a device (v3.7.5 at this time)
2. Open the attached ExcludedShareExtensions project
3. Build and run the project to the same device from #1
4. In the Share sheet that appears, tap more More and flip the switch for Tumblr to on
5. Observe that the Tumblr icon appears as a sharing option even though its activity type was included in excludedActivityTypes.

Expected Results:
The Tumblr sharing option should not be visible in the activity view controller.

Actual Results:
The Tumblr option is visible in the activity view controller even though it was specifically excluded.

iOS 8.1.2 (12B440)

A demo project is attached.

iPhone 5s (Model A1453, A1533)

'ExcludedShareExtensions.zip' was successfully uploaded.


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