[v2] Add tvOS support

[neilkimmett]

Some UIKit classes aren't available on tvOS (they're marked with __TVOS_PROHIBITED in the framework headers) so in order to build for tvOS we need to conditionally compile out any references to them. Also adds a tvOS library target in the Xcode project.

[neilkimmett]

Error from CI is

/usr/local/Homebrew/Library/Homebrew/brew.rb:12:in `<main>': Homebrew must be run under Ruby 2.3! (RuntimeError)
Error: No available formula with the name "applesimutils" 
==> Searching for a previously deleted formula...
Warning: homebrew/core is shallow clone. To get complete history run:
  git -C "$(brew --repo homebrew/core)" fetch --unshallow
Error: No previously deleted formula found.
==> Searching for similarly named formulae...
==> Searching local taps...
Error: No similarly named formulae found.
==> Searching taps...
==> Searching taps on GitHub...
Error: No formulae found in taps.
The command "source ./scripts/env/installAppleSimUtils.sh" failed and exited with 1 during .

which doesn't seem like its related to my change.

[neilkimmett]

Worth pointing out I've plucked this default value out of thin air; tvOS doesn't have a systemFontSize.

[gregorymfoster]

Looks like this is failing hides Tab Bar when pressing on Hide Top Bar and shows it when pressing on Show Top Bar, perhaps because the tvos does not support this functionality. Maybe we could modify some of the existing tests to skip the tvos target?

@gran33 What can we do to get this merged into the main repository?

[psegalen]

If someone could merge this, it would be great! 🙏

[yershalom]

Can one of the admins verify this patch?

[stale]

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[stale]

The issue has been closed for inactivity.

[itsmepetrov]

Hi @neilkimmett, do you have any plans to continue working on tvOS support? I would like to help you with it.

[neilkimmett]

@itsmepetrov hey alas I don't work on that app anymore, and we didn't even end up using this library, we used https://facebook.github.io/react-native/docs/tabbarios. I can help you with any questions you have tho. I gave a talk about that work last year which you might find useful http://kimmett.me/talks/react-native-on-tvos.html