How to pass Object Array on retrofit request?

 For passing Object Array on retrofit requestwe will use @FieldMap 

Create Object,

public class ItemsList {
    @SerializedName("id")
    private int id;
    @SerializedName("Amount")
    private int Amount;
    @SerializedName("Notes")
    private String Notes;
    @SerializedName("serviceId")
    private int serviceId;
    @SerializedName("TypeId")
    private int TypeId;
}

Create Object Array,

        Order.Orderitems orderitems;
        Map<String, String> parms = new HashMap<String, String>();
        for (int i = 0; i < orderItems.size(); i++) {
            orderitems = orderItems.get(i);
            parms.put("ItemsList[" + i + "][id]", String.valueOf(orderitems.getId()));
            parms.put("ItemsList[" + i + "][Amount]", String.valueOf(orderitems.getAmount()));
            parms.put("ItemsList[" + i + "][Notes]", "");
            parms.put("ItemsList[" + i + "][serviceId]", String.valueOf(orderitems.getServiceId()));
            parms.put("ItemsList[" + i + "][TypeId]", String.valueOf(orderitems.getServiceTypeId()));
        }

API  Call

@FormUrlEncoded
@POST("api/shidhin/UpdateOrder")
Call<CommonResponse> updateOrderItems(@Header("Authorization") String token, @Field("OrderId") int orderid, @FieldMap Map<String, String> parms);