Styling a search bar is hard. Lots of developers opt to build their own instead. If you do, remember to add the .searchField accessibility trait. VoiceOver will announce "Search Field" indicating the user that results might change as they type.
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The .selected accessibility trait indicates when an element has been selected. You’ll notice that VoiceOver announces “selected” before the accessibility label. You can find that in the system for the selected tab in the tab bar, for example.

If you need to send announcement notifications that can step into each other, they will by default, interrupt ongoing announcements. But you can pass attributed strings as parameters too, letting you specify announcements to be queued.

Make sure you support Dynamic Type up to the largest text size available. Take into account that there are five extra accessibility sizes available from the Accessibility Settings. It can make a huge difference for lots of users.
Content © Daniel Devesa Derksen-Staats on Accessibility up to 11! is licensed under CC BY 4.0. License details