Run digest cycle on graph's zoom and pan events

Rationale: we want to add "fit" and "zoom to central object" buttons
that should be visible when graph is not fitted or is not zoomed to
the center respectively. It's simple to write such conditions for
buttons but they need to be recalculated as the graph is zoomed or
panned.

dist/cytoscape-actionbar.js

@@ -1,9 +1,9 @@
-angular.module('cytoscape.actionbar', []).directive('cytoscapeActionbar', function() {
+angular.module('cytoscape.actionbar', []).directive('cytoscapeActionbar', ["$rootScope", function($rootScope) {
   return {
     template: "<div ng-class='options.actionbarClass' style=\"position: absolute; z-index: 1000\">\n    <span ng-repeat=\"item in options.items\" ng-click='item.action(cy, item)' ng-if='item.condition()'\n    ng-class='[options.actionItemClass, icon, item.icon]' data-container='body' bs-tooltip='item.tooltip'></span>\n</div>",
     link: function(scope) {
       return cytoscape('core', 'actionbar', function(options) {
-        var defaults;
+        var defaults, digestEvent, i, len, ref;
         defaults = {
           items: [],
           actionbarClass: 'ui-cytoscape-actionbar',
@@ -17,8 +17,15 @@ angular.module('cytoscape.actionbar', []).directive('cytoscapeActionbar', functi
             };
           }
         });
+        ref = ['zoom', 'pan'];
+        for (i = 0, len = ref.length; i < len; i++) {
+          digestEvent = ref[i];
+          this.on(digestEvent, function() {
+            return $rootScope.$apply();
+          });
+        }
         return scope.options = options;
       });
     }
   };
-});
+}]);

src/CytoscapeActionbar.coffee

@@ -1,4 +1,4 @@
-angular.module('cytoscape.actionbar', []).directive 'cytoscapeActionbar', ->
+angular.module('cytoscape.actionbar', []).directive 'cytoscapeActionbar', ($rootScope) ->
   template: """
     <div ng-class='options.actionbarClass' style="position: absolute; z-index: 1000">
         <span ng-repeat="item in options.items" ng-click='item.action(cy, item)' ng-if='item.condition()'
@@ -12,10 +12,12 @@ angular.module('cytoscape.actionbar', []).directive 'cytoscapeActionbar', ->
       (options) ->
         defaults =
           items: []
-          actionbarClass: 'ui-cytoscape-actionbar' 	# set a class name for the toolbar to help with styling
-          actionItemClass: 'action-item' 			# set a class name for a toolbar item to help with styling
+          actionbarClass: 'ui-cytoscape-actionbar' # set a class name for the toolbar to help with styling
+          actionItemClass: 'action-item' # set a class name for a toolbar item to help with styling
         angular.extend(defaults, options)
         angular.forEach(options.items, (item) ->
           if not item.condition then item.condition = -> true)
+        # run digest cycle on graph's zoom and pan events
+        @on(digestEvent, -> $rootScope.$apply()) for digestEvent in ['zoom', 'pan']
         scope.options = options
     )