Flutter中使用16进制Hex颜色值
- 发表于
- flutter
从 Dart 2.6.0开始，您可以为 Color 类创建一个扩展，该扩展允许您使用十六进制颜色字符串来创建 Color 对象:
为 Color 类创建一个扩展
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extension HexColor on Color { /// String is in the format "aabbcc" or "ffaabbcc" with an optional leading "#". static Color fromHex(String hexString) { final buffer = StringBuffer(); if (hexString.length == 6 || hexString.length == 7) buffer.write('ff'); buffer.write(hexString.replaceFirst('#', '')); return Color(int.parse(buffer.toString(), radix: 16)); } /// Prefixes a hash sign if [leadingHashSign] is set to `true` (default is `true`). String toHex({bool leadingHashSign = true}) => '${leadingHashSign ? '#' : ''}' '${alpha.toRadixString(16).padLeft(2, '0')}' '${red.toRadixString(16).padLeft(2, '0')}' '${green.toRadixString(16).padLeft(2, '0')}' '${blue.toRadixString(16).padLeft(2, '0')}'; } |
使用
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final Color color = HexColor.fromHex('#aabbcc'); print(color.toHex()); print(const Color(0xffaabbcc).toHex()); |
另一个构造函数
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class HexColor extends Color { static int _getColorFromHex(String hexColor) { hexColor = hexColor.toUpperCase().replaceAll("#", ""); if (hexColor.length == 6) { hexColor = "FF" + hexColor; } return int.parse(hexColor, radix: 16); } HexColor(final String hexColor) : super(_getColorFromHex(hexColor)); } |
使用
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Color color1 = HexColor("b74093"); Color color2 = HexColor("#b74093"); Color color3 = HexColor("#88b74093"); // If you wish to use ARGB format |
