flutter collapsed sliver app bar ios status bar

[Maximilian Scheffel]

I have a collapsed navbar in my app with the sliver package from Flutter. Just like on the website of Flutter. this works without problems. However, I would like it to look like the Facebook app for IOS. Now it is that the Navbar is completely gone while scrolling. but it should only disappear until the IOS status bar, and then there just leave an edge. Like in the Facebook app.

Sliver Collapsed Navbar: https://api.flutter.dev/flutter/material/SliverAppBar-class.html