ColorFiltered 颜色过滤

对图片的颜色过滤，好像上面蒙了一层颜色似的。

/// Flutter code sample for ColorFiltered

// These two images have two [ColorFilter]s applied with different [BlendMode]s,
// one with red color and [BlendMode.modulate] another with a grey color and [BlendMode.saturation].

import 'package:flutter/material.dart';

void main() => runApp(const MyApp());

/// This is the main application widget.
class MyApp extends StatelessWidget {
  const MyApp({Key? key}) : super(key: key);

  static const String _title = 'Flutter Code Sample';

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: _title,
      home: Scaffold(
        appBar: AppBar(title: const Text(_title)),
        body: const MyStatelessWidget(),
      ),
    );
  }
}

/// This is the stateless widget that the main application instantiates.
class MyStatelessWidget extends StatelessWidget {
  const MyStatelessWidget({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return SingleChildScrollView(
      child: Column(
        children: <Widget>[
          ColorFiltered(
            colorFilter: const ColorFilter.mode(
              Colors.red,
              BlendMode.modulate,
            ),
            child: Image.network(
                'https://flutter.github.io/assets-for-api-docs/assets/widgets/owl-2.jpg'),
          ),
          ColorFiltered(
            colorFilter: const ColorFilter.mode(
              Colors.grey,
              BlendMode.saturation,
            ),
            child: Image.network(
                'https://flutter.github.io/assets-for-api-docs/assets/widgets/owl.jpg'),
          ),
        ],
      ),
    );
  }
}