Gradient Text in Flutter

问题

I was wondering if it is possible to create a gradient over text Flutter. There is a gist of text gradient using Dart's ui, but it is kinda long and I was hoping to be simpler.

回答1:

Taken from here, you can use Text's style painter.

Create the shader,

final Shader linearGradient = LinearGradient(
  colors: <Color>[Color(0xffDA44bb), Color(0xff8921aa)],
).createShader(Rect.fromLTWH(0.0, 0.0, 200.0, 70.0));

then use it in the TextStyle's foreground

  Text(
        'Hello Gradients!',
        style: new TextStyle(
            fontSize: 60.0,
            fontWeight: FontWeight.bold,
            foreground: Paint()..shader = linearGradient),
      )

Source code

回答2:

You can use ShaderMask for that. Remember to set the Text's color to white and you're good

class GradientText extends StatelessWidget {
  GradientText(
    this.text, {
    @required this.gradient,
  });

  final String text;
  final Gradient gradient;

  @override
  Widget build(BuildContext context) {
    return ShaderMask(
      shaderCallback: (bounds) => gradient.createShader(
        Rect.fromLTWH(0, 0, bounds.width, bounds.height),
      ),
      child: Text(
        text,
        style: TextStyle(
          // The color must be set to white for this to work
          color: Colors.white,
          fontSize: 40,
        ),
      ),
    );
  }
}

Full example

class GradientTextWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: SizedBox.expand(
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.center,
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            GradientText(
              'Hello Flutter',
              gradient: LinearGradient(colors: [
                Colors.blue.shade400,
                Colors.blue.shade900,
              ]),
            ),
            GradientText(
              'Rainbow',
              gradient: LinearGradient(colors: [
                Colors.red,
                Colors.pink,
                Colors.purple,
                Colors.deepPurple,
                Colors.deepPurple,
                Colors.indigo,
                Colors.blue,
                Colors.lightBlue,
                Colors.cyan,
                Colors.teal,
                Colors.green,
                Colors.lightGreen,
                Colors.lime,
                Colors.yellow,
                Colors.amber,
                Colors.orange,
                Colors.deepOrange,
              ]),
            ),
            GradientText(
              'Fade out',
              gradient: LinearGradient(
                colors: [
                  Colors.black,
                  Colors.white,
                ],
                begin: Alignment.topLeft,
                end: Alignment.bottomRight,
              ),
            ),
          ],
        ),
      ),
    );
  }
}

来源：https://stackoverflow.com/questions/51686868/gradient-text-in-flutter