Parsing a JSON API response-CodePudding

An API is giving me a JSON response like so :

{
    "amountCredited":0,
    "isFirstOrder":false,
     "orderItems":[
       {
          "_id":624342e1c66be9001d501230,
          "status":2,
          "pinCode":749326,
          "kioskId":61bb3982089a66001db4ab77,
          "kioskActivityId":620668ad433322b99557c874
          }
       ]
}

I'm trying to access the data inside the "orderItems" in order to feed it to an existing parsing model in the App

order = OrderItemModel.fromJson(response.body['orderItems'] as Map<String, dynamic>);

but since the data inside orderItems JSON response is inside an array I can't access it this way..

How can I access it knowing that this JSON "orderItems" array will always only have one item as a response ?

Would something like response.body['orderItems' : [0]] enable me to access the first item data ?

CodePudding user response：

Since you always know that the array will always have only one item. We'll first make it a List & then access the first element.

order = OrderItemModel.fromJson((response.body['orderItems'] as List<dynamic>).first as Map<String, dynamic>);

To understand it a bit better refer to the code below:

The JSON response contains an array, which we need to access.

final ordersArray = response.body['orderItems'] as List<dynamic>;

Then we want to access the first order (according to the question)

final firstOrder = ordersArray.first as Map<String, dynamic>;

Once we have the order, we'll convert it to the model

final order = OrderItemModel.fromJson(firstOrder);

EDIT: as it was pointed out in a comment List objects have a getter called first which can be used to get the first element, the code has been updated with that.

CodePudding user response：

You need to convert as Map and List because Flutter deal only with this datatypes. For example:

Map order1 = {
          "_id":"624342e1c66be9001d501230",
          "status":2,
          "pinCode":749326,
          "kioskId":"61bb3982089a66001db4ab77",
          "kioskActivityId":"620668ad433322b99557c874"
          };
  Map order2 = {
          "_id":"224342e1c66be9001d501232",
          "status":1,
          "pinCode":248023,
          "kioskId":"41bb3982089a66001db4ab74",
          "kioskActivityId":"720668ad433322b99557c875"
          };
  Map m = {
    "amountCredited":0,
    "isFirstOrder":false,
     "orderItems":[
       order1,
       order2
       ]
};
  
  
  print(m['orderItems'][1]);
  print(m['orderItems'][1]['pinCode']);

The result will be:

 {_id: 224342e1c66be9001d501232, status: 1, pinCode: 248023, kioskId: 41bb3982089a66001db4ab74, kioskActivityId: 720668ad433322b99557c875}
248023