The argument type 'Diagnosticable' can't be assigned to the parameter type 'TextStyle?'. in compose.dart

[Sarat-1997]

Row(
children: [
Expanded(
child: TextField(
cursorHeight: 24,
style: TextStyle(fontSize: 18),
decoration: InputDecoration(
hintText: "Compose email",
border: InputBorder.none,
hintStyle: entered == false
? TextStyle(fontSize: 18, color: Colors.grey[700])
: Text(file?.name),
contentPadding: EdgeInsets.fromLTRB(20, 20, 20, 20)),
keyboardType: TextInputType.text,
),
)
],
),
And also not able to display file when we picking file on attachment icon. Is there any solution?