Debugging focus issues in your app
Find errors and determine why the next focused item isn’t what you expected.
Overview
With the use of indirect controls for your tvOS app, it’s imperative that focus works correctly. To help you find focus problems, Apple provides two debugging tools: UIFocusLoggingEnabled and UIFocusDebugger.
Turn on live focus logging
See how the focus engine determines which view is currently in focus by turning on live focus logging. As you move focus, the log updates, showing how the new view came into focus.
In your Xcode project, select Edit Scheme and add -UIFocusLoggingEnabled YES to the Arguments Passed On Launch section.
[Image]
On launch, the debugger logs all focus events and displays the events in the Xcode console and the Console app. The debugger updates the log as focus changes in your app.
[Image]
Find focus issues using UIFocusDebugger
The UIFocusDebugger class contains several methods to help you find focus issues. You don’t use this class or its methods directly from your code. Instead, during a debugging session, you call the methods of this class from the LLDB debugger command line to obtain information about the state of the focus system. For example, po UIFocusDebugger.status() returns the state of the focus engine.