Q:

How to use ngChange in custom directive

I want to create directive for toggle button, I have code that I want to put into directive:
<div class="toggle-button" ng-class="{true: toggleTrue === true, false: toggleTrue === false}">
    <button class="true" ng-click="toggleTrue = true">Y</button><button class="false" ng-click="toggleTrue = false">N</button>
</div>

(I only work on style change, that's why I have only class change)
I want to have something like:
<toogle ng-change="SomeFunction()" ng-model="someValue" />

how can I work with ng-change in my directive? Should I just parse attr or use scope attribute or is there a code like with ngModel that need to be use together with ngChange.

A:

By try and error I found code that work with ngModel and ngChange:
return {
    restrict: 'E',
    require: 'ngModel',
    scope: {},
    template: '<div class="toggle-button" ng-class="{true: toggleValue === true, false: toggleValue === false}">'+
        '<button class="true" ng-click="toggle(true)">Y</button>'+
        '<button class="false" ng-click="toggle(false)">N</button>'+
        '</div>',
    link: function(scope, element, attrs, ngModel) {
        ngModel.$viewChangeListeners.push(function() {
            scope.$eval(attrs.ngChange);
        });
        ngModel.$render = function() {
            scope.toggleValue = ngModel.$modelValue;
        };
        scope.toggle = function(toggle) {
            scope.toggleValue = toggle;
            ngModel.$setViewValue(toggle);
        };
    }
};

For unknow reason scope: true don't work (if I have $scope.toggle variable used as model, it try to execute that boolean instead of a function)

