How to set color shade for BoxDecoration in Container?-CodePudding

How to give color shade in BoxDecoration?

Container(
        decoration: const BoxDecoration(
          borderRadius: BorderRadius.all(Radius.circular(10)),
          //color: Color(0x64A3D7FF),        // <== this is working fine
          color: Colors.blue[100],           // <= Why this is giving me "Invalid constant value."
        ),
        alignment: Alignment.center,
        width: 210,
        height: 100,
)

CodePudding user response：

You are using const before BoxDecoration and using Colors.blue[100] means reading map and which is not compile time constant. It will get data on runtime.

You can explore the color,

 static const MaterialColor blue = MaterialColor(
    _bluePrimaryValue,
    <int, Color>{
       50: Color(0xFFE3F2FD),
      100: Color(0xFFBBDEFB),
      200: Color(0xFF90CAF9),
      300: Color(0xFF64B5F6),
      400: Color(0xFF42A5F5),
      500: Color(_bluePrimaryValue),
      600: Color(0xFF1E88E5),
      700: Color(0xFF1976D2),
      800: Color(0xFF1565C0),
      900: Color(0xFF0D47A1),
    },
  );

Therefore, you can not use const with color[value]

Container(
  decoration: BoxDecoration( // remove const
    borderRadius: BorderRadius.all(Radius.circular(10)),
    color: Colors.blue[100],
  ),

CodePudding user response：

Just Remove the const keyword used before the boxdecoration, and it will work correctly