courses/flutter-firebase/topics-screen/

[utterances-bot]

Topics Grid

Use a GridView to display a Firestore collection query

https://fireship.io/courses/flutter-firebase/firestore-data-model/

[OberstVonGatow]

This video ends with i'm going to create TopicItem but never showed how or at least the code for the file.
Not a big deal because it's on github but a strange ending.
https://github.com/fireship-io/flutter-firebase-quizapp-course/blob/master/lib/topics/topic_item.dart

[OberstVonGatow]

🙈 should have just watched the next video...

[tappella]

Independently of the TopicItem Widget or if you are rendering a Text Widget, you will probably face an issue when mapping the topics variable with the error:

" The method 'map' isn't defined for the type 'Object' "

It means, when setting the var topics, dart could not infer the type of its result. The instructor can correct me, please, that would be much appreciated.

I solved that by force casting the result of the data as the same as the getTopics method as below.

var topics = snapshot.data! as List;

With that you can map topics to the Text or Custom Widget of your preference.

topics.map((topic) => Text(topic.title)).toList()

[mack-raymond]

in case of "failed: Status{code=PERMISSION_DENIED, description=Missing or insufficient permissions., cause=null}", go to firestore rules and set "allow read, write: if true;"

[gael1130]

Independently of the TopicItem Widget or if you are rendering a Text Widget, you will probably face an issue when mapping the topics variable with the error:

" The method 'map' isn't defined for the type 'Object' "

It means, when setting the var topics, dart could not infer the type of its result. The instructor can correct me, please, that would be much appreciated.

I solved that by force casting the result of the data as the same as the getTopics method as below.

var topics = snapshot.data! as List;

With that you can map topics to the Text or Custom Widget of your preference.

topics.map((topic) => Text(topic.title)).toList()

@tappella I had the same issue, then saw the quick fix (ctrl + ;): add the models file.

import '../services/models.dart';

Once that file is imported, it will recognize that you defined the result of Topic in models.dart.
I hope that helps