Both CupertinoSliverNavigationBar and CupertinoNavigationBar should support background colors for the expanded and collapsed states. These colors could also be lerped when those states are in transition.

The second part of the original issue should be followed up on in #53788

OP:

Use case

Currently, CupertinoSliverNavigationBar does not support the following two things.

1. Different background colors for expanded and collapsed state.
2. Different titles for expanded and collapsed state. The use case could be using largeTitle: 'Profile' and middle: username for example. Currently, in expanded state both largeTitle and middle are shown, which I think is incorrect.
   • this second request is reflected in CupertinoSliverNavigationBar & CupertinoNavigationBar should support differing style||widget for largeTitle and middle #53788

Proposal

I propose that CupertinoSliverNavigationBar supports the following two things:

1. different background colors for expanded and collapsed state with possibility to animate the color change on scroll, and
2. different titles for expanded and collapsed state by either:
   • not showing middle property on expanded state (which I think should be the way to go), or
   • adding a bool showMiddleWhenExpanded property denoting whether middle should be present in expanded state as well (probably even better than the first option), or
   • adding another property title that is showed instead of largeTitle in collapsed state. This would mean that middle is only showed in expanded state which I think is not OK.
   • this second request is reflected in CupertinoSliverNavigationBar & CupertinoNavigationBar should support differing style||widget for largeTitle and middle #53788

The following video shows an example of animated color transition I would like to achieve.

Note

I am willing to implement this if it receives a green light, however details whether color change should be animated or not and which of the three options for point 2. is the best have to be discussed first.