How do I display sum of ng-repeat elements on their change?

Question

I have a ng-repeat generated set of <Select> which contain a numerical value. I want their overall numerical sum to be displayed whenever one <Select> is changed by the user. {{option.score}} represents the numerical value I wish to allot into a total.

Image:

https://cdn.pbrd.co/images/NGg0gJn.png

Template:

    <label class="item item-input item-select" ng-repeat="criteria in tool.criterias">
        <div class="input-label">
            {{criteria.desc}}
        </div>
        <select>
            <option ng-repeat="option in criteria.options">
                {{option.score}} &mdash; {{option.answer}}
            </option>
        </select>
    </label>
    ...
    <p>Total: the sum of all the option.score's</p>

Controller:

.controller('FullToolsCtrl', function ($scope, $stateParams, Tools) {
  $scope.tool = Tools.get($stateParams.toolId);
});

Data:

{
  "criterias": [
    {
      "desc": "Complexion",
      "options": [
        {
          "answer": "Blue or Pale all over",
          "score": "0"
        },
        {
          "answer": "Blue at extremities",
          "score": "1"
        },
        {
          "answer": "No cyanosed body or extremities",
          "score": "2"
        }
      ]
    },
    {
      "desc": "Pulse",
      "options": [
        {
          "answer": "Absent",
          "score": "0"
        },
        {
          "answer": "< 100",
          "score": "1"
        },
        {
          "answer": "> 100",
          "score": "2"
        }
      ]
    },
    {
      "desc": "Grimace",
      "options": [
        {
          "answer": "No response to stimulation",
          "score": "0"
        },
        {
          "answer": "Grimace on suction or aggressive stimulation",
          "score": "1"
        },
        {
          "answer": "Cry on stimulation",
          "score": "2"
        }
      ]
    },
    {
      "desc": "Activity",
      "options": [
        {
          "answer": "Absent",
          "score": "0"
        },
        {
          "answer": "Some flexion",
          "score": "1"
        },
        {
          "answer": "Flexed arms and legs resist extension",
          "score": "2"
        }
      ]
    },
    {
      "desc": "Respiratory effort",
      "options": [
        {
          "answer": "Absent",
          "score": "0"
        },
        {
          "answer": "Weak, irregular, gasping",
          "score": "1"
        },
        {
          "answer": "Strong, lusty cry",
          "score": "2"
        }
      ]
    }
  ],
  "desc": "Scoring tool for neonates.",
  "name": "APGAR Score"
}

Answer 1

There's nothing really built into ng-repeat to deal with this and you're actually outside of the ng-repeat construct when you want your total to appear. Generally you would just bind an expression in your HTML to a function call in your controller. Something like:

<p>Total: the sum of all the option.score's  {{total)()}}</p>

(where $ctrl is your controller).

Then in your controller you'd have a function mapped to it with something like:

$scope.total = function() { var total = 0 angular.forEach($scope. criteria.options, function(criteria) { total+= criteria.score } return total };

If you're using controllerAs syntax it'd be slighltly different.

Answer 2

try something like this:

 var app = angular.module("Demo", []); app.controller("AppController", function($scope) { $scope.total = 0; $scope.selectValue = []; $scope.SumValue = function() { $scope.total = 0 for (var i = 0; i < $scope.selectValue.length; i++) { if ($scope.selectValue[i] != undefined) $scope.total += parseInt($scope.selectValue[i]); } } $scope.data = { "criterias": [{ "desc": "Complexion", "options": [{ "answer": "Blue or Pale all over", "score": "0" }, { "answer": "Blue at extremities", "score": "1" }, { "answer": "No cyanosed body or extremities", "score": "2" }] }, { "desc": "Pulse", "options": [{ "answer": "Absent", "score": "0" }, { "answer": "< 100", "score": "1" }, { "answer": "> 100", "score": "2" }] }, { "desc": "Grimace", "options": [{ "answer": "No response to stimulation", "score": "0" }, { "answer": "Grimace on suction or aggressive stimulation", "score": "1" }, { "answer": "Cry on stimulation", "score": "2" }] }, { "desc": "Activity", "options": [{ "answer": "Absent", "score": "0" }, { "answer": "Some flexion", "score": "1" }, { "answer": "Flexed arms and legs resist extension", "score": "2" }] }, { "desc": "Respiratory effort", "options": [{ "answer": "Absent", "score": "0" }, { "answer": "Weak, irregular, gasping", "score": "1" }, { "answer": "Strong, lusty cry", "score": "2" }] }], "desc": "Scoring tool for neonates.", "name": "APGAR Score" } }); 

 <script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.23/angular.min.js"></script> <div ng-app="Demo"> <div ng-controller="AppController"> <div ng-repeat="criteria in data.criterias"> <label> {{ criteria.desc }} </label> <br/> <select ng-model="selectValue[$index]" ng-change="SumValue()"> <option ng-repeat="option in criteria.options" value="{{option.score}}">{{option.answer}}</option> </select> </div> <p>Total: the sum of all the option.score's {{ total }}</p> </div> </div> 

JSFiddle: https://jsfiddle.net/d42jeuvs/15/

Hope this is what you wanted. Thanks.