RadioButton web control with Knockout.js and MVVM

Here is an example of a RadioButton control using Knockout and MVVM. Hope this helps anyone looking.

<!-- Step 1 - Create the HTML File or the View -->
<!DOCTYPE html>
<html>
<head>
    <!-- Step 2 - Include jquery and knockout -->
    <script type="text/javascript" src="http://code.jquery.com/jquery-latest.pack.js"></script>
    <script type="text/javascript" src="http://knockoutjs.com/downloads/knockout-3.0.0.js"></script>
     
    <!-- Step 3 - Add script to run when page loads -->
    <script type="text/javascript" >
        $(document).ready(function(){
 
            <!-- Step 4 - Add a RadioButtonModel -->
            var RadioButtonModel = function(parent, inText, inValue, inGroupName, canClickMethod) {
                    // Private
                    var _self = this;
                    var _canClickMethod = (canClickMethod) ? canClickMethod : function() { return true; };
                    var _parent = parent;

                    // Public
                    this.text = ko.observable(inText);
                    this.value = ko.observable(inValue);
                    this.group = ko.observable(inGroupName);
                    this.class = ko.observable();
                    this.isSelected = ko.computed(function() {
                        return (_parent && _parent.selectedValue) ? _parent.selectedValue() == _self.value() : false;
                    }, _self);
                    _self.canClick = ko.computed(function() { return _canClickMethod(); });
                };
                
                
            <!-- Step 5 - Add a RadioButtonViewModel -->
            var RadioButtonViewModel = function (rbLabels, rbValues, group, defaultValue) {
                // Private
                var _self = this;
                var _rbLables = rbLabels;
                var _rbValues = rbValues;
                var _group = group;
                var _defaultValue = defaultValue;                

                // Public
                _self.selectedValue = ko.observable(_defaultValue);
                
                _self.list = ko.observableArray();
                for (var i = 0; i < _rbLables.length; i++) {
                    _self.list.push(new RadioButtonModel(_self, _rbLables[i], _rbValues[i], _group));
                }

                _self.selectedIndex = ko.computed(function () {
                    var i = 0;
                    var foundIndex = -1;
                    ko.utils.arrayForEach(_self.list(), function (item) {
                        if (_self.selectedValue() == item.value()) {
                            foundIndex = i;
                        }
                        i++;
                    });
                    return foundIndex;
                }, _self);

                _self.selectedText = ko.computed(function () {
                    return (_self.list()[_self.selectedIndex()]) ? _self.list()[_self.selectedIndex()].text() : "";
                }, _self);
                
                _self.clear = function(value){
                    _self.selectedValue(value ? value : "");
                }
                
            }
 
            <!-- Step 6 - Create ViewModel for whatever you need -->
            function SurveyAnswerViewModel() {
                var self = this;
                 
                <!-- Step 7 - Create an observable list instance -->
                self.rbGroup1 = new RadioButtonViewModel(new Array("Good", "Average", "Poor"), new Array(10,5,1), "Group1", 10);                           
                 
                <!-- Step 8 - Create a computed value to require a selection before submitting -->
                self.canClick = ko.computed( function() {
                    return self.rbGroup1.selectedValue() != "";
                }, self);
                
                <!-- Step 9 - Make some button methods for this example -->
                self.submitClick = function(){
                    // Do something here
                }
                
                self.resetClick = function(){
                    self.rbGroup1.clear();
                }                 
            }
            
            <!-- Step 10 - Create a computed value to require a selection before submitting -->   
            ko.applyBindings(new SurveyAnswerViewModel());
        });
    </script>
</head>
<body>
    <!-- Step 11 - Create a div containing the html for one radio button and bind to foreach: list -->
    <div data-bind="foreach: rbGroup1.list">
        <div>
            <input type="radio" data-bind="attr: {name: group}, value: value, checked: $root.rbGroup1.selectedValue, checkedValue: value" />
            <span data-bind="text: $index() + '. ' + text()"></span>
            <span data-bind="text: 'Is selected: ' + isSelected()"></span>
        </div>
    </div>
    <br />
    
    <!-- Step 12 - Add html elements to see other properties -->
    <p data-bind="text: rbGroup1.selectedValue"></p>
    <p data-bind="text: rbGroup1.selectedText"></p>
     
    <!-- Step 13 - Add a button and bind its to methods -->
    <button type="submit" id="btnSubmit" data-bind="enable: canClick, click: submitClick">Submit</button>
    <button type="reset" id="btnReset" data-bind="enable: canClick, click: resetClick">Reset</button>
 
</body>
</html>

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