This is a Sliver AppBar.
How can I change the color of the back arrow ?
BUT I don't want to set leading: Icon(Icons.arrow_back, color: Colors.red)
since (I believe) that the Sliver AppBar has the nice property of adapting the lead icon depending on context.
wrap the SliverAppBar widget with Theme widget, and change primaryIconTheme color in ThemeData. Here's the code: