保持Flutter的样式独立/独立于视图代码

时间:2019-11-22 17:20:19

标签: flutter flutter-layout flutter-dependencies

所以这就是我今天设计简单的颤动按钮的方式-

FlatButton(
          child: Text('Hello'),
          onPressed: () {},
          color: Colors.blue,
          colorBrightness: Brightness.dark, 
          disabledColor: Colors.blueGrey,
          highlightColor: Colors.red,
          padding: EdgeInsets.symmetric(
              horizontal: 8.0, vertical: 5.0)
        )

似乎颤振的视图代码要求每个组件都内置样式?我怎样才能完全分开?像什么CSS(几乎)用于网络?似乎代码会更加简洁,我也可以重用我的样式。

我可以将诸如Brightness类之类的子类派生为自定义亮度,但是这似乎有点过头了。

此外,今天还找到了这个软件包,它使我更接近想要的东西-https://pub.dev/packages/division

理想情况下,有什么好的做法可以使样式与视图代码分离而扑朔迷离?

谢谢!

3 个答案:

答案 0 :(得分:1)

也许您可能知道,但是您可以在main.dart中声明通用样式,

  

对于Button主题,

 ThemeData(
...

 buttonTheme: ButtonThemeData(
        shape:
            RoundedRectangleBorder(borderRadius: BorderRadius.circular(8.0)),
        colorScheme: colorSchemeDark,
        splashColor: AppColors.themeColor.shade900,
        height: 50,
        highlightColor: AppColors.themeColor.shade800,
        textTheme: ButtonTextTheme.primary,
      ),
)
  

对于卡片主题,

ThemeData(
...

 cardTheme: CardTheme(
        margin: EdgeInsets.only(top: 8, left: 8, right: 8, bottom: 8),
        elevation: 6.0,
        shape: RoundedRectangleBorder(
          borderRadius: BorderRadius.circular(8.0),
        ),
      ),
)

我创建了一个gist here

答案 1 :(得分:1)

解决方案1 ​​

您可以使用默认样式创建可重复使用的FlattButon,并且可以随时更改样式:

示例:

class MyFlatButton extends StatelessWidget {
  const MyFlatButton({
    Key key,
    @required this.text,
    @required this.onPressed,
    this.color = Colors.blue, // set default Values
    this.colorBrightness = Brightness.dark, //
    this.disabledColor = Colors.blueGrey, //
    this.highlightColor = Colors.red, //
    this.padding =
        const EdgeInsets.symmetric(horizontal: 8.0, vertical: 5.0), //
  }) : super(key: key);

  final String text;
  final VoidCallback onPressed;
  final Color color;
  final Brightness colorBrightness;
  final MaterialColor disabledColor;
  final MaterialColor highlightColor;
  final EdgeInsetsGeometry padding;
  @override
  Widget build(BuildContext context) {
    return FlatButton(
      child: Text(
        '$text',
      ),
      onPressed: onPressed,
      color: color,
      colorBrightness: colorBrightness,
      disabledColor: disabledColor,
      highlightColor: highlightColor,
      padding: padding,
    );
  }
}

,您可以像MyFlatButton一样使用它,而不是在您的应用程序中使用FlatButton

  child: MyFlatButton(
    text: 'Hello',
    onPressed: () {},
    color: Colors.cyan,
  ),

解决方案2

如果您想“完全”分离样式,则可以创建一个额外的类来保存样式

class MyFlatButton2 extends StatelessWidget {
  const MyFlatButton2({
    Key key,
    @required this.text,
    @required this.onPressed,
    this.styles = const ButtonStyles(),
  }) : super(key: key);

  final String text;
  final VoidCallback onPressed;
  final ButtonStyles styles;
  @override
  Widget build(BuildContext context) {
    final btnStyles = ButtonStyles();
    return FlatButton(
      child: Text('$text'),
      onPressed: onPressed,
      color: styles.color ?? btnStyles.color,
      colorBrightness: styles.colorBrightness ?? btnStyles.colorBrightness,
      disabledColor: styles.disabledColor ?? btnStyles.disabledColor, 
      highlightColor: styles.highlightColor ?? btnStyles.highlightColor, 
      padding: styles.padding ?? btnStyles.padding,
    ); 
  }
}

// Styles Class
class ButtonStyles {
  final Color color;
  final Brightness colorBrightness;
  final MaterialColor disabledColor;
  final MaterialColor highlightColor;
  final EdgeInsetsGeometry padding;

  const ButtonStyles({
    this.color = Colors.blue, // set default Values
    this.colorBrightness = Brightness.dark, //
    this.disabledColor = Colors.blueGrey, //
    this.highlightColor = Colors.red, //
    this.padding =
        const EdgeInsets.symmetric(horizontal: 8.0, vertical: 5.0), //
  });
}

然后您可以使用它 默认样式

  child: MyFlatButton2(
    text: 'Hello',
    onPressed: () {},
  ),

或者您可以覆盖样式

  child: MyFlatButton2(
    text: 'Hello',
    onPressed: () {},
    styles: ButtonStyles(
      colorBrightness: Brightness.dark,
      color: Colors.green,
      padding: EdgeInsets.all(20),
    ),
  ),

其他,您还可以使用一些具有预定义样式的命名构造函数

  factory ButtonStyles.predefinedStyle1() => ButtonStyles(
        color: Colors.green, // set default Values
        colorBrightness: Brightness.light, //
        disabledColor: Colors.red, //
        highlightColor: Colors.red, //
        padding: const EdgeInsets.symmetric(horizontal: 18.0, vertical: 15.0),
  );

然后

  child: MyFlatButton2(
    text: 'Hello',
    onPressed: () {},
    styles: ButtonStyles.predefinedStyle1(),
  ),

答案 2 :(得分:0)

使用此软件包https://pub.dev/packages/division

它允许您为小部件创建样式,将其存储以供重复使用等等。

final textStyle = TxtStyle()
  ..textColor(Colors.white)
  ..fontSize(30)
  ..bold()
  ..italic()
  ..textAlign.start();

Text(
'hi',
style:textStyle
)