KvadrantPageHeader

The top of a Windows Phone page: a small application title and an oversized page title beneath it, both in the content and both scrolling away with it.

This is not a top app bar and the difference is the point. Metro has no bar: the title is text in the flow, so it leaves the screen as you scroll and gives the page its height back. Reaching for TopAppBar here produces a Material screen wearing Metro's colours.

The margins are the template's: the title panel sits at 12,17,0,28 and the page title is pulled up by 7 px inside it — 9,-7,0,0. That negative number is not a mistake to tidy away; it is how the two titles end up as close together as they are.

Right-to-left needs nothing here, and that is checked rather than assumed (B-41). The asymmetric margins are padding(start = …) and a vertical offset, both of which Compose mirrors on its own, so rtl/page header shows the title against the right margin with no code for it. Said here because the next person asking will otherwise re-check all three of the custom layouts, and this is the one that was free.