Added "on-shown" attribute

src/uiSelectController.js

@@ -112,6 +112,10 @@ uis.controller('uiSelectCtrl',
 
       $scope.$broadcast('uis:activate');
 
+      $timeout(function(){
+        ctrl.onShowCallback($scope);
+      });
+
       ctrl.open = true;
 
       ctrl.activeIndex = ctrl.activeIndex >= ctrl.items.length ? 0 : ctrl.activeIndex;

src/uiSelectDirective.js

@@ -59,6 +59,7 @@ uis.directive('uiSelect',
 
         $select.onSelectCallback = $parse(attrs.onSelect);
         $select.onRemoveCallback = $parse(attrs.onRemove);
+        $select.onShowCallback = $parse(attrs.onShow);
 
         //Limit the number of selections allowed
         $select.limit = (angular.isDefined(attrs.limit)) ? parseInt(attrs.limit, 10) : undefined;

test/select.spec.js

@@ -1207,6 +1207,28 @@ describe('ui-select tests', function() {
 
   });
 
+  it('should invoke show callback on activate', function () {
+    scope.onShowFn = function (someArg) {
+      scope.someArg = someArg;
+    };
+    var el = compileTemplate(
+      '<ui-select on-show="onShowFn(\'shown\')" ng-model="selection.selected"> \
+        <ui-select-match placeholder="Pick one...">{{$select.selected.name}}</ui-select-match> \
+        <ui-select-choices repeat="person.name as person in people | filter: $select.search"> \
+          <div ng-bind-html="person.name | highlight: $select.search"></div> \
+          <div ng-bind-html="person.email | highlight: $select.search"></div> \
+        </ui-select-choices> \
+      </ui-select>'
+    );
+
+    expect(scope.someArg).toBeFalsy();
+    clickMatch(el);
+    $timeout.flush();
+
+    expect(scope.someArg).toEqual('shown');
+  });
+
+
   it('should set $item & $model correctly when invoking callback on select and no single prop. binding', function () {
 
     scope.onSelectFn = function ($item, $model, $label) {