我不认为您可以将渐变传递给AppBar，因为它期望使用Color而不是渐变。
但是，您可以创建自己的小部件来模仿AppBar，除非使用渐变。请看一下我从Planets-Flutter教程中拼凑而成的示例及其下面的代码。
import "package:flutter/material.dart";class Page extends StatelessWidget { @override Widget build(BuildContext context) { return Column(children : <Widget>[GradientAppBar("Custom Gradient App Bar"), Container()],); }}class GradientAppBar extends StatelessWidget { final String title; final double barHeight = 50.0; GradientAppBar(this.title); @override Widget build(BuildContext context) { final double statusbarHeight = MediaQuery .of(context) .padding .top; return new Container( padding: EdgeInsets.only(top: statusbarHeight), height: statusbarHeight + barHeight, child: Center( child: Text( title, style: TextStyle(fontSize: 20.0, color: Colors.white, fontWeight: FontWeight.bold), ), ), decoration: BoxDecoration( gradient: LinearGradient( colors: [Colors.red, Colors.blue], begin: const FractionalOffset(0.0, 0.0), end: const FractionalOffset(0.5, 0.0), stops: [0.0, 1.0], tileMode: TileMode.clamp ), ), ); }}希望这可以帮助。如果您有任何问题，请告诉我。
