Q:

Toggle class with ng-click on several elements

How can I toggle classes on several elements individually with ng-click?
In this question https://stackoverflow.com/a/22072110/2169327 toggling classes with a click was done like this:
CSS:
.red {
    color: red;
}

JS:
$scope.toggle = false;

HTML:
<button id="btn" ng-click="toggle = !toggle" ng-class="{'red' : toggle}">Change Class</button>

But what if I have several buttons that each should toggle its own class with ng-click? 
If I set it up in this way:
HTML:
<button id="btn" ng-click="toggle = !toggle" ng-class="{'red' : toggle}">Change Class</button>
<button id="btn2" ng-click="toggle = !toggle" ng-class="{'red' : toggle}">Change Class</button>

Both buttons get toggled if I press one.
I know a workaround is to define an own ng-click event for each button (f.ex toggle1 for button1, toggle2 for button2) - but is this the best way?

A:

I made simple directive for testing:
module.directive('toggleClass', function() {
    return {
        restrict: 'A',
        link: function(scope, element, attrs) {
            element.bind('click', function() {
                element.toggleClass(attrs.toggleClass);
            });
        }
    };
});

so you can make any element toggle class you need
<button id="btn" toggle-class="active">Change Class</button>
<div toggle-class="whatever"></div>

A:

Depending on your requirements, you may be able to use an ng-repeat with an array representing the toggles. For example:
Your view:
<div ng-repeat="toggle in toggles">
    <button id="btn" ng-click="toggle.state = !toggle.state" ng-class="{'red' : toggle.state}">Change Class</button>
</div>

Inside your controller:
$scope.toggles = [{ state: true }, { state: false }, { state: true }];

This way you can expand on your button set by simply updating the array, or the internal array objects (should you need more complexity).

