LocusIdCompat

An identifier for an unique state (locus) in the application. Should be stable across reboots and backup / restore.

Locus is a new concept introduced on Android Q and it lets the intelligence service provided by the Android system correlate state between different subsystems such as content capture, shortcuts, and notifications.

For example, if your app provides an activity representing a chat between 2 users (say A and B, this chat state could be represented by:

LocusIdCompat chatId = new LocusIdCompat("Chat_A_B");

And then you should use that chatId by:

• Setting it in the chat notification (through NotificationCompat.Builder.setLocusId(chatId)).
• Setting it into the androidx.core.content.pm.ShortcutInfoCompat (through ShortcutInfoCompat.Builder.setLocusId(chatId)), if you provide a launcher shortcut for that chat conversation.
• Associating it with the android.view.contentcapture.ContentCaptureContext of the root view of the chat conversation activity (through getContentCaptureSession, then new ContentCaptureContext.Builder(chatId).build() and setContentCaptureContext - see android.view.contentcapture.ContentCaptureManager for more info about content capture).
• Configuring your app to launch the chat conversation through the ACTION_VIEW_LOCUS intent.