Flutter: Functions with Argument in Raised Button - flutter

Question

I am trying to pass parameters to Function on Raised Button click. I am using ListView Builder and Raised Button.
Widget buildList(BuildContext context, int index) {
return Container(
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(25),
color: Colors.white,
),
width: double.infinity,
height: 100,
margin: EdgeInsets.symmetric(vertical: 10, horizontal: 10),
padding: EdgeInsets.symmetric(vertical: 10, horizontal: 10),
child: Row(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Container(
width: 70,
height: 70,
margin: EdgeInsets.only(top:5, right: 5, bottom: 5),
child: CircleAvatar(
radius: 50,
backgroundColor: Color(0xff476cfb),
child: ClipOval(
child: Image.network(
lists[index].profilePhoto,
fit: BoxFit.fill,
),
),
),
),
Expanded(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text(
lists[index].name,
style: TextStyle(
color: primary,
fontWeight: FontWeight.bold,
fontSize: 18),
),
SizedBox(
height: 6,
),
Row(
children: <Widget>[
Icon(
Icons.location_on,
color: secondary,
size: 20,
),
SizedBox(
width: 5,
),
Text(
lists[index].baseLocation + ", " + lists[index].country,
style: TextStyle(
color: primary, fontSize: 13, letterSpacing: .3)),
],
),
SizedBox(
height: 6,
),
Row(
children: <Widget>[
Icon(
Icons.timer,
color: secondary,
size: 20,
),
SizedBox(
width: 5,
),
Text(
lists[index].registrationDate ,
style: TextStyle(
color: primary, fontSize: 13, letterSpacing: .3)),
],
),
],
),
),
ButtonTheme(
minWidth: 40.0,
height: 100.0,
child: RaisedButton(
onPressed: _unfollow(lists[index].uid),
color: Colors.redAccent,
textColor: Colors.white,
child: Text(
'Unfollow',
style: new TextStyle(
fontSize: 12.0,
color: Colors.white,
),
),
),
)
],
),
);
}
Problem is my buttons are inactive/disabled (grayed out).
Here is the Function which I am creating.
_unfollow(int unfollowid) {
int unFollowid = unfollowid;
print(unFollowid);
}
I want to get the Id on button click. So, I can perform the async activity. I an open to other ways of handling such scenarios if necessary.

Answer 1

Missing () =>, Please replace below code in RaisedButton
onPressed: () => _unfollow(lists[index].uid)

Answer 2

try this
onPressed:(){ _unfollow(lists[index].uid)},