Flutter - How to insert the ad in every nth row (every 4th row) in listview.separated - flutter

Question

I am using Listview.separated and I am using google_mobile_ads as the package to integrate the ads. I followed the example here but dint get the exact what I needed.
I called the banner ad in separatorBuilder but that either gives the divider or the ad after every nth row.
I need insert the after every 4th row in the listview.separated.
ListView.separated(
scrollDirection: Axis.vertical,
shrinkWrap: true,
controller: _scrollController,
itemCount: articleslist.length + 1,
itemBuilder: (BuildContext context, int index) {
if (index == articleslist.length) {
_loading = true;
return Center(
child: Row(
children: [
Container(
padding: EdgeInsets.all(5),
child: CircularProgressIndicator(
color: Colors.deepOrange[800],
),
),
SizedBox(
width: 15,
),
Text(
'Articles are being loaded...',
style: TextStyle(color: Colors.deepOrange[800]),
)
],
),
);
} else {
Text(
'No data to load',
style: TextStyle(color: Colors.deepOrange[800]),
);
}
if (articleslist.length == 0) {
return Container(
child: Center(
child: Text('Loading...',
style: TextStyle(color: Colors.deepOrange))));
} else {
var imgUrl = articleslist[index].img.toString();
imgUrl = BaseUrl + imgUrl.toString();
var title = articleslist[index].title;
title = title.replaceAll(RegExp(r'<[^>]*>'), '');
var body = articleslist[index].body;
body = body.replaceAll(RegExp(r'<[^>]*>'), '');
return InkWell(
onTap: () {
print('Tapped : ${articleslist[index].nid}');
print(index);
Navigator.push(
context,
new MaterialPageRoute(
builder: (context) => DetailPage(
articleslist[index].title,
articleslist[index].img,
articleslist[index].nid,
articleslist[index].uid,
articleslist[index].created,
)));
},
child: Container(
padding: EdgeInsets.fromLTRB(8.0, 6.0, 8.0, 0.0),
child: Row(
// crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
Container(
width: 120,
height: 75,
child: ClipRRect(
borderRadius: BorderRadius.circular(8),
child: imgUrl == 'No img'
? Image.asset('images/placeholder.png',
height: 220, fit: BoxFit.cover)
: FadeInImage.assetNetwork(
placeholder: 'images/placeholder.png',
image: imgUrl,
height: 220,
fit: BoxFit.cover,
),
),
),
const SizedBox(
width: 20,
),
Expanded(
child: Column(
mainAxisAlignment:
MainAxisAlignment.spaceBetween,
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text(
title,
style: TextStyle(
color: Colors.black, fontSize: 16),
),
const SizedBox(
height: 10,
),
Text(
'author : $uid',
style: TextStyle(
fontSize: 10,
),
),
const SizedBox(
height: 5,
),
Text(
created,
style: TextStyle(
fontSize: 10,
),
)
],
),
),
],
),
),
);
}
},
separatorBuilder: (context, index) => Divider(),
),

Answer 1

You can add a item nth place using ListView.separated and '%' operator.
You just change from number '4' after '%' operator to what you want to add to nth place.
...
if ((index + 1) % 4 == 0) {
...
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
visualDensity: VisualDensity.adaptivePlatformDensity,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
FocusNode focusNode = FocusNode();
#override
void initState() {
super.initState();
focusNode.addListener(() {
print('1: ${focusNode.hasFocus}');
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: _buildBody(),
);
}
Widget _buildBody() {
return ListView.separated(
itemCount: 20,
separatorBuilder: (context, index) {
if ((index + 1) % 4 == 0) {
return Container(
height: 100,
color: Colors.yellow,
child: Text('it is ads'),
);
} else {
return Container();
}
},
itemBuilder: (context, index) {
return Container(
height: 100,
color: Colors.blue,
child: Text('item index: $index'),
);
},
);
}
}