sizedbox. expand code example

Example 1: set width card flutter

SizedBox(
        width: double.infinity,
        height: 300,
        child: Card(
          elevation: 2,
          child: Text("test")
         ),
      )

Example 2: sizedbox flutter

SizedBox(
                  height: 100,
                  width: 100,
                  child: Center(
                    child: CircularProgressIndicator(),
                  ),
                )