I want to exclude Weibo and WeChat, and set the following code:

let av = UIActivityViewController(activityItems: items, applicationActivities:nil)
av.excludedActivityTypes = [.postToWeibo, .postToTencentWeibo]
self.present(av, animated: true)

No matter what I did, the two apps still show up on UIActivityViewController. But excluding mail and copyToPasteboard are both work

av.excludedActivityTypes = [.postToWeibo, .postToTencentWeibo, .copyToPasteboard, .mail]

Any other way to exclude them? Thanks