How to sum of all Map values except one Key's value-CodePudding

For a learning I have created a list of Map ..I want to sum all of the key's value except month number like...in short I want to make loop for key's value

for seeing output.i have taken list tile where title should show some of expenses and leading shows month number

{
 'Month':1,
'Lightbill':305,
'Provisional':503,
}

Now I want like this

1 808

here is my basic code

import 'package:flutter/material.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {


  List<Map<String,int>> mylist=[
    {
      'Month':1,
      'Provisional': 4500,
      'Teaexp': 980,
      'Lightbill': 1240,
      'Assets': 399,
    },

    { 'Month':2,
      'Provisional': 0250,
      'Teaexp': 150,
      'Lightbill': 240,
      'Assets': 30,
    }
  ];
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: SafeArea(
          child: Column(
            children: List.generate(mylist.length, (index) {
              int sum=0;
              sum=sum int.parse(mylist[index]['Provisional'].toString());
              
              return Container(
                child: ListTile(
                  leading:CircleAvatar(child:
                    Text(mylist[index]['Month'].toString()),),

                  title: Text(sum.toString()),
                ),
              );
            }),
          ),
        ),
      ),
    );
  }
}

CodePudding user response：

i am assuming all the map value are non null and has type int. you can achieve like it -

Text(
"${(mylist[index]["Lightbill"] as int)    (mylist[index]["Provisional"] as int)  (mylist[index]["Teaexp"] as int)}"
)

CodePudding user response：

You can get all values like myMap.values and to skip 1st I am using .skip() and then to sum up using reduce.

final sum = mylist[index]
    .values
    .skip(1)
    .reduce((value, element) => value   element);

More about Map and List

CodePudding user response：

You could use this:

Text((mylist[index].values.sum - mylist[index]['Month']!).toString())

This needs

import 'package:collection/collection.dart';

to use sum

CodePudding user response：

Yet another way to do it would be to use the keys property to retrieve a list of all keys and filter it:

int sum(Map<String, int> input) {
  int sum = 0;
  input
    .keys
    .where((String key) => key != 'Month')
    .forEach((String key) => sum  = input[key]);
  return sum;
}