<com.google.android.material.progressindicator.CircularProgressIndicator app:indicatorColor="@color/primaryColor" />

默认情况下，它从Themedata继承了accentColor

  void main() => runApp(new MaterialApp(
  theme: ThemeData(
                 primaryColor: Colors.blue,
                 accentColor:  Colors.blueAccent,
                 //This will be the color for CircularProgressIndicator color
               ),
  home: Homepage()
    ));

你可以用你的新颜色改变这个accentColor属性。 另一种方法是像这样使用预定义的主题数据

void main() => runApp(new MaterialApp(
  theme: ThemeData.light().copyWith(
                 accentColor:  Colors.blueAccent,
                 //change the color for CircularProgressIndicator color here
               ),
  home: Homepage()
    ));

或者，您可以直接在CircularProgressIndicator中更改此颜色属性，如下所示

CircularProgressIndicator(
         valueColor: AlwaysStoppedAnimation<Color>(Colors.red),
                    ),

backgroundColor设置浅色，它看到像浅色背景色的圆，valueColor它是加载颜色，它将显示编译加载圆超过灰色

 CircularProgressIndicator(
        backgroundColor: Colors.gray,
        valueColor: AlwaysStoppedAnimation<Color>(Colors.black)
        )

像这样使用——>

CircularProgressIndicator (valueColor: AlwaysStoppedAnimation (Colors.grey [500]),)),

对于单色集合，

 CircularProgressIndicator(
     valueColor:AlwaysStoppedAnimation<Color>(Colors.red),
   );

适用于多种颜色变换/设置。

class MyApp extends StatefulWidget {
      @override
      _MyHomePageState createState() => _MyHomePageState();
    }
    
    class _MyHomePageState extends State<MyApp> with TickerProviderStateMixin {
      AnimationController animationController;
      @override
      void dispose() {
        // TODO: implement dispose
        super.dispose();
        animationController.dispose();
      }
      @override
      void initState() {
        super.initState();
        animationController =
            AnimationController(duration: new Duration(seconds: 2), vsync: this);
        animationController.repeat();
      }
    
      @override
      Widget build(BuildContext context) {
        return Scaffold(
          appBar: AppBar(
            title: Text("Color Change CircularProgressIndicator"),
          ),
          body:  Center(
            child: CircularProgressIndicator(
              valueColor: animationController
                  .drive(ColorTween(begin: Colors.blueAccent, end: Colors.red)),
            ),
          ),
        );
      }
    }

试试这个:

CircularProgressIndicator(
  color: Colors.yellow, // Change your color here
),