[移动开发]flutter HEX 色值，转换成RGBO 格式

话不多说，直接上代码，拿过去就能使用

static Color hexStringColor(String colorString, {double alpha = 1}) {
    if (alpha < 0) {
      alpha = 0;
    } else if (alpha > 1) {
      alpha = 1;
    }
    String colorStr = colorString;
    if (!colorStr.startsWith('0xff') && colorStr.length == 6) {
      colorStr = '0xff' + colorStr;
    }
    if (colorStr.startsWith('0x') && colorStr.length == 8) {
      colorStr = colorStr.replaceRange(0, 2, '0xff');
    }
    if (colorStr.startsWith('#') && colorStr.length == 7) {
      colorStr = colorStr.replaceRange(0, 1, '0xff');
    }
    Color color = Color(int.parse(colorStr));
    int red = color.red;
    int green = color.green;
    int blue = color.blue;
    return Color.fromRGBO(red, green, blue, alpha);
  }