commit 92ba355d407c4f2817aa469fa9f6ecaa512a3394
author ginnnnnnny <ginnyhuang@chromium.org> Tue Apr 08 20:45:10 2025
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> Tue Apr 08 20:45:10 2025
tree 081523c5bcb5dd6617dba39c00e31eb8f6ffd62b
parent 2d671ecca1b34740a22fdb61e23715a46fd876d1

[iOS][CUI1] Refactor browser view's visibility state

Discover Feed Launch (CUI1) needs to know when the NTP is hidden by
other views or modals on top of it (especially search related ones).
To achieve this purpose, and to also increase code readability (having
both "self. visible" and "self.viewVisible" could be confusing) we
make "visibility" a state.

The new view lifecycle -> state would be as follows:

- before `viewWillAppear`: kNotInViewHierarchy
- between `viewWillAppear` and `viewDidAppear`: kAppearing
- between `viewDidAppear` and `viewWillDisappear`:
    - if the view is visible (or covered by a model not presented by
bvc), it would be `kVisible`
    - otherwise it would most likely by `kCoveredBy*`
- after `viewWillDisappear`: kNotInViewHierarchy

The list of states is not conclusive, as there are plenty of other
views that may appear on the top of the browser view controller and
not notify it. For the purpose of CUI we just need to make sure that
it's covered by omnibox popup, but the more the merrier.

Bug: 406544789
Change-Id: If299ec96fefecd630b901e15f40ccc454e15d0f2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6430846
Commit-Queue: Ginny Huang <ginnyhuang@chromium.org>
Reviewed-by: Federica Germinario <fedegermi@google.com>
Reviewed-by: Mark Cogan <marq@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1444352}