How to get a checkbox value from response by using Angular js

1. I am trying to add a checkbox value in database and its work perfect.

2. The problem is if I need to check a checkbox after getting result from response its showing the checked value as -1 but i need a checkbox value as 0,1,2 etc.

3. If i click a checked box value its index value must be changed to -1 only but its changing as 0 or some other value

Below my code

HTML:

<div ng-repeat="tag in edit_tag_list">
<input type="checkbox" ng-model="tag.selected" id="{{tag.id}}" value="{{tag.id}}" ng-checked="selectionTagList.indexOf(tag.id) > -1" ng-click="toggleSelection(tag.id)" style="cursor: pointer;" ng-true-value="checked" ng-false-value="">
<input type="checkbox" ng-model="tag.selected" id="{{tag.id}}" value="{{tag.id}}" ng-checked="tag.checked='yes'" ng-click="toggleSelection(tag.id)" style="cursor: pointer;" ng-true-value="checked" ng-false-value="">

JS:

$scope.toggleSelection=function(tageName){
    var idx=$scope.selectionTagList.indexOf(tageName);
        if(idx > -1)
        {
            $scope.selectionTagList.splice(idx,1);
        }
        else
        {
            $scope.selectionTagList.push(tageName);
        }

console.log($scope.selectionTagList);};