Flutter - Firebase - 无法获取数据

Question

It's my notification page on my social media app, but when i open that page it does not show anything, just working (circularProgress()) which is mean there is no data in database, but there is a data. It just cant get that data, Could you please help me about it?

I tried to update everything. My flutter version is 1.24.0-3.0.pre

There is no problem about connection between app and database because i can get another data at another pages.

Is it related or not I dont know but I got this error:

6.26.0 - [Firebase/Firestore][I-FST000001] WatchStream (6000010b0818) Stream error: 'Unavailable: Operation timed out' [VERBOSE-2:profiler_metrics_ios.mm(186)] Error retrieving thread information: (os/kern) invalid argument

This one is my previous code which is similar to original one but it does not work.

import 'package:pga/pages/home.dart';
import 'package:pga/pages/post_screen.dart';
import 'package:pga/pages/profile.dart';
import 'package:pga/widgets/header.dart';
import 'package:pga/widgets/progress.dart';
import 'package:cached_network_image/cached_network_image.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter/material.dart';
import 'package:timeago/timeago.dart' as timeago;

class ActivityFeed extends StatefulWidget {
  @override
  _ActivityFeedState createState() => _ActivityFeedState();
}

class _ActivityFeedState extends State<ActivityFeed> {
  getActivityFeed() async {
    QuerySnapshot snapshot = await activityFeedRef
        .doc(currentUser.id)
        .collection('feedItems')
        .orderBy('timestamp', descending: true)
        .limit(50)
        .get();
    List<ActivityFeedItem> feedItems = [];
    snapshot.docs.forEach((doc) {
      feedItems.add(ActivityFeedItem.fromDocument(doc));
      //print('Activity Feed Item: ${doc.data}');
    });
    return feedItems;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.white70,
      appBar: header(context, titleText: "Bildirimler"),
      body: Container(
          child: FutureBuilder(
        future: getActivityFeed(),
        builder: (context, snapshot) {
          if (!snapshot.hasData) {
            return circularProgress();
          } else {
            return ListView(
              children: snapshot.data,
            );
          }
        },
      )),
    );
  }
}

Widget mediaPreview;
String activityItemText;

class ActivityFeedItem extends StatelessWidget {
  final String username;
  final String userId;
  final String type; // 'like', 'follow', 'comment'
  final String mediaUrl;
  final String postId;
  final String userProfileImg;
  final String commentData;
  final Timestamp timestamp;

  ActivityFeedItem({
    this.username,
    this.userId,
    this.type,
    this.mediaUrl,
    this.postId,
    this.userProfileImg,
    this.commentData,
    this.timestamp,
  });

  factory ActivityFeedItem.fromDocument(DocumentSnapshot doc) {
    return ActivityFeedItem(
      username: doc['username'],
      userId: doc['userId'],
      type: doc['type'],
      postId: doc['postId'],
      userProfileImg: doc['userProfileImg'],
      commentData: doc['commentData'],
      timestamp: doc['timestamp'],
      mediaUrl: doc['mediaUrl'],
    );
  }

  showPost(context) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => PostScreen(
          postId: postId,
          userId: userId, //currentUser.id,
        ),
      ),
    );
  }

  configureMediaPreview(context) {
    if (type == "like" || type == 'comment') {
      mediaPreview = GestureDetector(
        onTap: () => showPost(context),
        child: Container(
          height: 50.0,
          width: 50.0,
          child: AspectRatio(
              aspectRatio: 16 / 9,
              child: Container(
                decoration: BoxDecoration(
                  image: DecorationImage(
                    fit: BoxFit.cover,
                    image: CachedNetworkImageProvider(mediaUrl),
                  ),
                ),
              )),
        ),
      );
    } else {
      mediaPreview = Text('');
    }

    if (type == 'like') {
      activityItemText = "Gönderini Beğendi";
    } else if (type == 'follow') {
      activityItemText = "Seni Takip Ediyor";
    } else if (type == 'comment') {
      activityItemText = "Yorum Yaptı: $commentData";
    } else {
      activityItemText = "Error: Unknown type '$type'";
    }
  }

  @override
  Widget build(BuildContext context) {
    configureMediaPreview(context);

    return Padding(
      padding: EdgeInsets.only(bottom: 2.0),
      child: Container(
        color: Colors.white54,
        child: ListTile(
          title: GestureDetector(
            onTap: () => showProfile(context, profileId: userId),
            child: RichText(
              overflow: TextOverflow.ellipsis,
              text: TextSpan(
                  style: TextStyle(
                    fontSize: 14.0,
                    color: Colors.black,
                  ),
                  children: [
                    TextSpan(
                      text: username,
                      style: TextStyle(fontWeight: FontWeight.bold),
                    ),
                    TextSpan(
                      text: ' $activityItemText',
                    ),
                  ]),
            ),
          ),
          leading: CircleAvatar(
            backgroundImage: CachedNetworkImageProvider(userProfileImg),
          ),
          subtitle: Text(
            timeago.format(timestamp.toDate()),
            overflow: TextOverflow.ellipsis,
          ),
          trailing: mediaPreview,
        ),
      ),
    );
  }
}

showProfile(BuildContext context, {String profileId}) {
  Navigator.push(
      context,
      MaterialPageRoute(
          builder: (context) => Profile(
                profileId: profileId,
              )));
}

And this one is my updated code after @Lakshmi Narayanan suggestion, which is still not working.

import 'package:pga/pages/home.dart';
import 'package:pga/pages/post_screen.dart';
import 'package:pga/pages/profile.dart';
import 'package:pga/widgets/header.dart';
import 'package:pga/widgets/progress.dart';
import 'package:cached_network_image/cached_network_image.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter/material.dart';
import 'package:timeago/timeago.dart' as timeago;

class ActivityFeed extends StatefulWidget {
  @override
  _ActivityFeedState createState() => _ActivityFeedState();
}

class _ActivityFeedState extends State<ActivityFeed> {
  List<ActivityFeedItem> feedItemsList = [];
  int feedCount = 0;

  getActivityFeed() async {
    QuerySnapshot snapshot = await activityFeedRef
        .doc(currentUser.id)
        .collection('feedItems')
        .orderBy('timestamp', descending: true)
        .limit(50)
        .get();
    List<ActivityFeedItem> feedItems = [];
    snapshot.docs.forEach((doc) {
      feedItems.add(ActivityFeedItem.fromDocument(doc));
    });
    return feedItems;
  }

  feedItems() {
    return Container(
      child: FutureBuilder(
        future: getActivityFeed(),
        builder: (context, snapshot) {
          if (!snapshot.hasData) {
            return circularProgress();
          } else {
            return ListView(
              children: snapshot.data,
            );
          }
        },
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.white70,
      appBar: header(context, titleText: "Bildirimler"),
      body: ListView(
        shrinkWrap: true,
        children: <Widget>[
          feedItems(),
        ],
      ),
    );
  }
}

Widget mediaPreview;
String activityItemText;

class ActivityFeedItem extends StatelessWidget {
  final String feedId;
  final String username;
  final String userId;
  final String type; // 'like', 'follow', 'comment'
  final String mediaUrl;
  final String postId;
  final String userProfileImg;
  final String commentData;
  final Timestamp timestamp;

  ActivityFeedItem({
    this.feedId,
    this.username,
    this.userId,
    this.type,
    this.mediaUrl,
    this.postId,
    this.userProfileImg,
    this.commentData,
    this.timestamp,
  });

  factory ActivityFeedItem.fromDocument(DocumentSnapshot doc) {
    return ActivityFeedItem(
        username: doc['username'],
        userId: doc['userId'],
        type: doc['type'],
        postId: doc['postId'],
        userProfileImg: doc['userProfileImg'],
        commentData: doc['commentData'],
        timestamp: doc['timestamp'],
        mediaUrl: doc['mediaUrl'],
        feedId: doc['feedId']);
  }

  showPost(context) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => PostScreen(
          postId: postId,
          userId: userId, //currentUser.id,
        ),
      ),
    );
  }

  configureMediaPreview(context) {
    if (type == "like" || type == 'comment') {
      mediaPreview = GestureDetector(
        onTap: () => showPost(context),
        child: Container(
          height: 50.0,
          width: 50.0,
          child: AspectRatio(
              aspectRatio: 16 / 9,
              child: Container(
                decoration: BoxDecoration(
                  image: DecorationImage(
                    fit: BoxFit.cover,
                    image: CachedNetworkImageProvider(mediaUrl),
                  ),
                ),
              )),
        ),
      );
    } else {
      mediaPreview = Text('');
    }

    if (type == 'like') {
      activityItemText = "Hayalini Beğendi";
    } else if (type == 'follow') {
      activityItemText = "Seni Takip Ediyor";
    } else if (type == 'comment') {
      activityItemText = "Yorum Yaptı: $commentData";
    } else {
      activityItemText = "Error: Unknown type '$type'";
    }
  }

  @override
  Widget build(BuildContext context) {
    configureMediaPreview(context);

    return Padding(
      padding: EdgeInsets.only(bottom: 2.0),
      child: Container(
        color: Colors.white54,
        child: ListTile(
          title: GestureDetector(
            onTap: () => showProfile(context, profileId: userId),
            child: RichText(
              overflow: TextOverflow.ellipsis,
              text: TextSpan(
                  style: TextStyle(
                    fontSize: 14.0,
                    color: Colors.black,
                  ),
                  children: [
                    TextSpan(
                      text: username,
                      style: TextStyle(fontWeight: FontWeight.bold),
                    ),
                    TextSpan(
                      text: ' $activityItemText',
                    ),
                  ]),
            ),
          ),
          leading: CircleAvatar(
            backgroundImage: CachedNetworkImageProvider(userProfileImg),
          ),
          subtitle: Text(
            timeago.format(timestamp.toDate()),
            overflow: TextOverflow.ellipsis,
          ),
          trailing: mediaPreview,
        ),
      ),
    );
  }
}

showProfile(BuildContext context, {String profileId}) {
  Navigator.push(
      context,
      MaterialPageRoute(
          builder: (context) => Profile(
                profileId: profileId,
              )));
}

And this one is the original code which is from my Udemy course.

import 'package:cached_network_image/cached_network_image.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter/material.dart';
import 'package:fluttershare/pages/home.dart';
import 'package:fluttershare/pages/post_screen.dart';
import 'package:fluttershare/pages/profile.dart';
import 'package:fluttershare/widgets/header.dart';
import 'package:fluttershare/widgets/progress.dart';
import 'package:timeago/timeago.dart' as timeago;

class ActivityFeed extends StatefulWidget {
  @override
  _ActivityFeedState createState() => _ActivityFeedState();
}

class _ActivityFeedState extends State<ActivityFeed> {
  getActivityFeed() async {
    QuerySnapshot snapshot = await activityFeedRef
        .document(currentUser.id)
        .collection('feedItems')
        .orderBy('timestamp', descending: true)
        .limit(50)
        .getDocuments();
    List<ActivityFeedItem> feedItems = [];
    snapshot.documents.forEach((doc) {
      feedItems.add(ActivityFeedItem.fromDocument(doc));
      // print('Activity Feed Item: ${doc.data}');
    });
    return feedItems;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.orange,
      appBar: header(context, titleText: "Activity Feed"),
      body: Container(
          child: FutureBuilder(
        future: getActivityFeed(),
        builder: (context, snapshot) {
          if (!snapshot.hasData) {
            return circularProgress();
          }
          return ListView(
            children: snapshot.data,
          );
        },
      )),
    );
  }
}

Widget mediaPreview;
String activityItemText;

class ActivityFeedItem extends StatelessWidget {
  final String username;
  final String userId;
  final String type; // 'like', 'follow', 'comment'
  final String mediaUrl;
  final String postId;
  final String userProfileImg;
  final String commentData;
  final Timestamp timestamp;

  ActivityFeedItem({
    this.username,
    this.userId,
    this.type,
    this.mediaUrl,
    this.postId,
    this.userProfileImg,
    this.commentData,
    this.timestamp,
  });

  factory ActivityFeedItem.fromDocument(DocumentSnapshot doc) {
    return ActivityFeedItem(
      username: doc['username'],
      userId: doc['userId'],
      type: doc['type'],
      postId: doc['postId'],
      userProfileImg: doc['userProfileImg'],
      commentData: doc['commentData'],
      timestamp: doc['timestamp'],
      mediaUrl: doc['mediaUrl'],
    );
  }

  showPost(context) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => PostScreen(
          postId: postId,
          userId: userId,
        ),
      ),
    );
  }

  configureMediaPreview(context) {
    if (type == "like" || type == 'comment') {
      mediaPreview = GestureDetector(
        onTap: () => showPost(context),
        child: Container(
          height: 50.0,
          width: 50.0,
          child: AspectRatio(
              aspectRatio: 16 / 9,
              child: Container(
                decoration: BoxDecoration(
                  image: DecorationImage(
                    fit: BoxFit.cover,
                    image: CachedNetworkImageProvider(mediaUrl),
                  ),
                ),
              )),
        ),
      );
    } else {
      mediaPreview = Text('');
    }

    if (type == 'like') {
      activityItemText = "liked your post";
    } else if (type == 'follow') {
      activityItemText = "is following you";
    } else if (type == 'comment') {
      activityItemText = 'replied: $commentData';
    } else {
      activityItemText = "Error: Unknown type '$type'";
    }
  }

  @override
  Widget build(BuildContext context) {
    configureMediaPreview(context);

    return Padding(
      padding: EdgeInsets.only(bottom: 2.0),
      child: Container(
        color: Colors.white54,
        child: ListTile(
          title: GestureDetector(
            onTap: () => showProfile(context, profileId: userId),
            child: RichText(
              overflow: TextOverflow.ellipsis,
              text: TextSpan(
                  style: TextStyle(
                    fontSize: 14.0,
                    color: Colors.black,
                  ),
                  children: [
                    TextSpan(
                      text: username,
                      style: TextStyle(fontWeight: FontWeight.bold),
                    ),
                    TextSpan(
                      text: ' $activityItemText',
                    ),
                  ]),
            ),
          ),
          leading: CircleAvatar(
            backgroundImage: CachedNetworkImageProvider(userProfileImg),
          ),
          subtitle: Text(
            timeago.format(timestamp.toDate()),
            overflow: TextOverflow.ellipsis,
          ),
          trailing: mediaPreview,
        ),
      ),
    );
  }
}

showProfile(BuildContext context, {String profileId}) {
  Navigator.push(
    context,
    MaterialPageRoute(
      builder: (context) => Profile(
        profileId: profileId,
      ),
    ),
  );
}

Answer 1

There is nothing wrong with the code..

Since I have also worked with this code(Course from Udemy) @Raşid The thing is if a user likes your post,a document gets added into the feed collection in the cloud firestore and then the activityfeed notification will be filled with data.

How are you testing this out?

1. Are you liking your own post and trying to get it into the activity feed

(OR)

2. other user likes your post

Ans 1) Go to your post.dart and then comment out(Uncomment it after testing..)

// if (isNotPostOwner)

from both addLikeToActivityFeed() & removeLikeToActivityFeed() then check it out,

Ans 2) Try the first one, it should probably be the case. Else, I got no choices..

Answer 2

Try to put this,

feedItems(){
 return Container(
          child: FutureBuilder(
        future: getActivityFeed(),
        builder: (context, snapshot) {
          if (!snapshot.hasData) {
     ------->       return circularProgress();
          } else {
     ------->       return ListView(
              children: snapshot.data,
            );
          }
        },
      ),
);
}

in a seperate function and then trying calling it, ie,

 return Scaffold(
      
      body: ListView(
        shrinkWrap: true,
        children: <Widget>[   
          feedItems(),
        ],
      ),
    );
  }
}