[SOLVED] What would be Dart data type for a String Array attribute in a database collection ?

I tried List<String> but function errors out

"Type '_GrowableList<dynamic> is not a subtype of 'List<String>'

Anyone can share a quick sample of a dart cloud function to read from and write to an string array attribute in a collection.

TL;DR

Solution: The Dart data type for a String Array attribute in a database collection would be `List<String>`. If you encounter an error like "Type '_GrowableList<dynamic> is not a subtype of 'List<String>'," you can try using `value.cast<String>();` or defaulting to an empty list if the value is null. Here's an example of how to read from and write to a string array attribute in a collection using a Dart cloud function: To read from a string array attribute: ```dart List<String> x = document.data['array_attribute'].cast<String>(); ``` To write to a string array

you can do value.cast<String>(); but it might be better to be more defensive and check if value were null and default to an empty list.

Sorry but I would need more then that. I currently getDocument and then

List<String> x = received document.data['array_attribute']

So what do I change ?

Apologies for dumbing it down

Like so

TypeScript

  List<dynamic> dList = ['First string', 'And another'];

  List<String> stringList = dynamiclist.cast<String>();

So in your example you can do

TypeScript

  List<String> data =  document.data['array_attribute'].cast<String>();

@punti_z did you get your question resolved or still needed help? checking to see if we should close or not 🙂

[Closed] What would be Dart data type for a String Array attribute in a database collection ?