'snapshot.data.docs.length not working on flutter
I make some listview and it have likes and comments section. I want to show how many likes and comments that post had. The like section works by displaying the number of users who like it, i try to show it with snapshot.data.docs.length.toString() from firestore but when i try to show how many comments with same code as like section it not working and only get 0.
Padding(
padding: const EdgeInsets.only(top: 8),
child: Padding(
padding: const EdgeInsets.only(left: 15),
child: Row(
mainAxisAlignment:
MainAxisAlignment.spaceEvenly,
children: [
Container(
width: 80.0,
child: Row(
mainAxisAlignment:
MainAxisAlignment.start,
children: [
GestureDetector(
onLongPress: () {
Provider.of<PostFunction>(context,
listen: false)
.showLikes(
context,
documentSnapshot
.data()['title']);
},
onTap: () {
print('Adding like...');
Provider.of<PostFunction>(context,
listen: false)
.addLike(
context,
documentSnapshot
.data()['title'],
Provider.of<AuthenticationService>(
context,
listen: false)
.getUserUid);
},
child: Icon(
FontAwesomeIcons.arrowAltCircleUp,
color: kGreyColor,
size: 18.0,
),
),
StreamBuilder<QuerySnapshot>(
stream: FirebaseFirestore.instance
.collection('posts')
.doc(documentSnapshot
.data()['title'])
.collection('likes')
.snapshots(),
builder: (context, snapshot) {
if (snapshot.connectionState ==
ConnectionState.waiting) {
return Center(
child:
CircularProgressIndicator());
} else {
return Padding(
padding:
const EdgeInsets.only(
left: 8.0),
child: RichText(
text: TextSpan(
text: snapshot
.data.docs.length
.toString(),
style: GoogleFonts
.openSans(
color:
kGreyColor,
fontSize: 16.0),
children: <TextSpan>[
TextSpan(
text: ' votes',
style: GoogleFonts
.openSans(
color:
kGreyColor,
fontSize: 16.0,
)),
]),
),
);
}
})
],
),
),
SizedBox(width: 20),
Container(
width: 150.0,
child: Row(
mainAxisAlignment:
MainAxisAlignment.start,
children: [
GestureDetector(
onTap: () {
Provider.of<PostFunction>(context,
listen: false)
.showComments(
context,
documentSnapshot,
documentSnapshot
.data()['title']);
},
child: Icon(
FontAwesomeIcons.solidComments,
color: kGreyColor,
size: 16.0,
),
),
StreamBuilder<QuerySnapshot>(
stream: FirebaseFirestore.instance
.collection(' posts')
.doc(documentSnapshot
.data()['title'])
.collection('comments')
.snapshots(),
builder: (context, snapshot) {
if (snapshot.connectionState ==
ConnectionState.waiting) {
return Center(
child:
CircularProgressIndicator());
} else {
return Padding(
padding:
const EdgeInsets.only(
left: 8.0),
child: Text(
snapshot.data.docs.length
.toString(),
style: GoogleFonts.openSans(
color: kGreyColor,
fontSize: 16.0),
),
);
}
}),
],
),
),
Spacer(),
Provider.of<AuthenticationService>(context,
listen: false)
.getUserUid ==
documentSnapshot.data()['useruid']
? IconButton(
icon: Icon(EvaIcons.moreVertical,
color: kGreyColor, size: 16),
onPressed: () {
Provider.of<PostFunction>(context,
listen: false)
.showPostOptions(
context,
documentSnapshot
.data()['title']);
})
: Container(width: 0.0, height: 0.0)
],
),
),
),
Solution 1:[1]
Replace .collection(' posts')
with .collection('posts')
in the “comments” section of the Streambuilder.
Your stream data is coming as empty as the database cannot find a collection with name (“ posts”). So when you try to show how many comments the post had with the same code as the “likes” section it is not working and only getting 0 each time.
Solution 2:[2]
Could you please try this one?
StreamBuilder(
stream: firestoreDB,
builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot) {
if (!snapshot.hasData) {
return Center(child: CircularProgressIndicator());
}
return ListView.builder(
itemCount: snapshot.data!.size,
itemBuilder: (context, index) {
return Card(
child: ListTile(
title: Text(snapshot.data!.docs[index]['name']),
subtitle: Text(snapshot.data!.docs[index]['description']),
),
);
},
);
},
),
Solution 3:[3]
just declare the dataType of builder's arguments..i mean, builder:(BuildContext context,AsyncSnapshot snapShot).check the image
Sources
This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.
Source: Stack Overflow
| Solution | Source |
|---|---|
| Solution 1 | Priyashree Bhadra |
| Solution 2 | enzo |
| Solution 3 | jb_jason |

