编辑个人资料页面上的Angularjs复选框值

I am new to angularjs and getting some problem on checkbox values on edit profile page.

I have an array for checkbox

$scope.checkBoxes = [
        {id:'1', value:'Reading'},
        {id:'2', value:'Cooking'},
        {id:'3', value:'Dancing'},
        {id:'4', value:'Singing'}
];

and I have used ng-repeat for showing checkbox

<div ng-repeat="checkBox in checkBoxes" style="display:inline;">
    <input type="checkbox" ng-model="checkBox.selected" id={{checkBox.id}}' ng-checked="checkItem(checkBox.id)" ng-change="listActionsHandler(checkBoxes)">{{ checkBox.value }}
</div>

This is my ng-change function:

$scope.listActionsHandler = function(list) {
        var has = [];
        angular.forEach(list, function(item) {
            if ( angular.isDefined(item.selected) && item.selected === true ) {
                has.push(item.id);
            }
        });
        formData['hobby'] = has;
 }

and this is my ng-checked function that is used for showing checkbox checked according to database saved value.

var arr_checked_items = data.data.hobby;
var arraySize = arr_checked_items.length;
$scope.checkItem = function (id) {
    var checked = false;
    for(var i=0; i<= arraySize; i++) {
        if(id == arr_checked_items[i]) {
                checked = true;
        }
    }
    return checked;
};

These function work properly on add and edit page, but problem is that when I doesn't apply any changes on checkbox and click on submit button it take blank value.

My question is that: if I does not apply any changes, it should take old value of checkbox and if I apply any changes, it should take new value of checkbox.

Please try with below code. I am not sure weather it is working or not.

$scope.checkItem = function (id) {
    var checked = "";
    for(var i=0; i<= arraySize; i++) {
        if(id == arr_checked_items[i]) {
                checked = "checked";
        }
    }
    return checked;
};