Flutter Exception on JSON-CodePudding

Error : type '(dynamic) => Null' is not a subtype of type '(String, dynamic) => void'

Hello guys I am new to flutter and I fetch my data from firebase store and pass to my model, but this error happened! so can you please explain why this happen and how i can i solve this problem,

MainModel.fromJson(dynamic json) {
    if (json['tax_center'] != null) {
      print(json['tax_center']); //{address: New York, name: centeral}
      _taxCenter = [];
      json['tax_center'].forEach((v) {
        _taxCenter?.add(Tax_center.fromJson(v));
      });
    }
...

Thanks for your time!

CodePudding user response：

Through print I could see that json['tax_center'] returns Map and not a list.

Using forEach you are treating it as a list.

Try doing something like this:

if (json['tax_center'] != null) {
      print(json['tax_center']); //{address: New York, name: centeral}
      _taxCenter = [];
      _taxCenter?.add(Tax_center.fromJson(json['tax_center']));
}

CodePudding user response：

MainModel.fromJson(json) { //don't use key type
    if (json['tax_center'] != null) {
      print(json['tax_center']); //{address: New York, name: centeral}
      _taxCenter = [];
      json['tax_center'].forEach((v) {
        _taxCenter?.add(Tax_center.fromJson(v));
      });
    }