Flutter error: type '_Smi' is not a subtype of type 'double'

Question

I developed a app using flutter 1.0. The app works well on most android and ios phones. But I found there one android phone and one iphone can not open that app, just show the error message "type '_Smi' is not a subtype of type 'double'". Is there someone can tell me what's going on my app.

Error picture when open the flutter app:

Answer 1

It's hard to tell without the relevant piece of code, but in my case, this happened when trying to assign a double value from a Map. The solution was simply to call .toDouble on the value:

// myMap is a Map<String, dynamic>
double myDouble = myMap['mykey'].toDouble();

It used to work without the .toDouble(), but the _Smi error started happening one day.

Answer 2

I think running flutter clean should solve this problem. I always run that when changing the phone.

Answer 3

_Smi stands for Small machine integers, according to Dart Cookbook

So basically you're getting an int and parsing it incorrectly.

Answer 4

这帮助我从另一个 api 读取 json。

double temp = weatherData['main']['temp'].toDouble();

Answer 5

dynamic更改，而不是double

Answer 6

when you are using firestore (from google firebase) and you are having fields in a document that are stored as number (only number available, so number is used for int, double, float, ...) - make sure that you use .toDouble() before assigning the field value of a document to a double field in your model class in dart.

Example:

final collectionReference =
        FirebaseFirestore.instance.collection("Products");

final products = await collectionReference.get();

List productsDocuments = products.docs
        .map((doc) => doc.data())
        .toList();

items = Items.fromList(productsDocuments);

List<Item> items;
  factory Items.fromList(docsFirebase) => Items(
      items: List<Item>.from(docsFirebase.map((docFirebase) => Item(
          itemName: docFirebase['item_name'],
          variantId: docFirebase['variant_id'],
          imageUrl: docFirebase['image_url'],
          barcode: docFirebase['barcode'],
          defaultPrice: docFirebase['default_price'].toDouble(),
          lowStock: docFirebase['low_stock'],
          optimalStock: docFirebase['optimal_stock']))));
}

Answer 7

I had the same problem and settled on this.

Try to replace this:

double myDouble = myMap['mykey'].toDouble();

To this:

double myDouble = double.parse(myMap['mykey'].toString());