Nutrient
The document title overlay — a separate strip rendered below the main toolbar row that shows the current document's title centered. It is the Compose successor of the legacy pspdf__activity_title_overlay TextView.
This is its own composable (so it can be reused or hosted on its own — see nutrientDocumentTitleOverlayComposeView for a View wrapper), but the SDK composes it inside NutrientMainToolbar, directly under the toolbar row, the same way the inline search bar lives inside the toolbar. It does not replace the toolbar row's own title (com.pspdfkit.compose
.toolbar.state.ToolbarFrame.title); both can be shown.
State comes from coordinator's ToolbarCoordinator.documentTitleOverlay; nothing is rendered when the overlay is not visible or has no title. Colors come from the main-toolbar scheme's com.pspdfkit.compose.theme.MainToolbarColors.documentTitleOverlay, which by default reuses the toolbar background and title text color and resolves from either the Compose theme or XML.