如何从指令元素中删除Angular Watcher？

Question

I have a directive that looks like this:

app.directive('mydirective', function($compile,$document){
    var directive = {
        restrict: 'EA',
        scope:{
        },
        link: link, 
    };  
    return directive; 

    function link(scope, element, attr) {
        var template_html = "<div id=\"popup\">{{popupTitle}}</div>";
        var template = angular.element(template_html);

        element.bind('click', function(){
                if(!$("#popup").is(':visible')){
                    var $popup = $compile(template)(scope);
                    $document.find('body').append($popup);
                }else{
                    $("#popup").remove();
                }
            });

        template.remove();

    }
});

The code works fine showing up and removing the popup element when clicking on mydirective . But, the problem is everytime when the element shows & hide, the angular watcher is just keep on increasing. The number of watcher increase is depending on the number of binding in template_html .

How can I get those watcher to be removed when popup is removed so that watchers will not accumulate increase over time.

Answer 1

Have you tried destroy the scope inside the else block when the popup is being removed?

    element.bind('click', function(){
        if(!$("#popup").is(':visible')){
            var $popup = $compile(template)(scope);
            $document.find('body').append($popup);
        }else{
            $("#popup").remove();
            scope.$destroy();
        }
    });

To create a new scope you could do something like

var popupScope;
element.bind('click', function(){
    if(!$("#popup").is(':visible')){
        popupScope = $scope.$new();
        var $popup = $compile(template)(popupScope);
        $document.find('body').append($popup);
    }else{
        $("#popup").remove();
        popupScope.$destory();
    }
});

Answer 2

Store your watcher in your controller as a variable:

var myWatcher = $scope.$watch(......

And make sure your controller is accessible from your directive, then you can call myWatcher() which will unbind your watcher since calling watch will return an unbound function.