Adds another childrenOf option to clearing tree cache to clear a cached branch, this is used to fix U4-3465 Media tree not updating when creating folders and can be used elsewhere where modifying trees outside of it's context.

src/Umbraco.Web.UI.Client/src/common/services/tree.service.js

@@ -126,6 +126,27 @@ function treeService($q, treeResource, iconHelper, notificationsService, $rootSc
                         treeCache = _.omit(treeCache, cacheKey);
                     }
                 }
+                else if (args.childrenOf) {
+                    //if childrenOf is supplied a cacheKey must be supplied as well
+                    if (!args.cacheKey) {
+                        throw "args.cacheKey is required if args.childrenOf is supplied";
+                    }
+                    //this will clear out all children for the parentId passed in to this parameter, we'll 
+                    // do this by recursing and specifying a filter
+                    var self = this;
+                    this.clearCache({
+                        cacheKey: args.cacheKey,
+                        filter: function(cc) {
+                            //get the new parent node from the tree cache
+                            var parent = self.getDescendantNode(cc.root, args.childrenOf);                            
+                            //clear it's children and set to not expanded
+                            parent.children = null;
+                            parent.expanded = false;
+                            //return the cache to be saved
+                            return cc;
+                        }
+                    });
+                }
                 else if (args.filter && angular.isFunction(args.filter)) {
                     //if a filter is supplied a cacheKey must be supplied as well
                     if (!args.cacheKey) {

src/Umbraco.Web.UI.Client/src/views/common/dialogs/mediapicker.controller.js

@@ -1,7 +1,7 @@
 //used for the media picker dialog
 angular.module("umbraco")
     .controller("Umbraco.Dialogs.MediaPickerController",
-        function($scope, mediaResource, umbRequestHelper, entityResource, $log, imageHelper, eventsService) {
+        function($scope, mediaResource, umbRequestHelper, entityResource, $log, imageHelper, eventsService, treeService) {
 
             var dialogOptions = $scope.$parent.dialogOptions;
             $scope.options = {
@@ -21,6 +21,12 @@ angular.module("umbraco")
                         .addFolder($scope.newFolderName, $scope.options.formData.currentFolder)
                         .then(function(data) {
 
+                            //we've added a new folder so lets clear the tree cache for that specific item
+                            treeService.clearCache({
+                                cacheKey: "__media", //this is the main media tree cache key
+                                childrenOf: data.parentId //clear the children of the parent
+                            });
+
                             $scope.gotoFolder(data.id);
                         });
                 }

src/Umbraco.Web.UI.Client/test/unit/common/services/tree-service.spec.js

@@ -262,6 +262,36 @@ describe('tree service tests', function () {
 
             expect(cache.__content.root.children.length).toBe(3);
         });
+        
+        it('removes cache children for a parent id specified', function () {
+
+            var cache;
+
+            treeService.getTree({ section: "content", cacheKey: "_" }).then(function (dd) {
+                treeService.loadNodeChildren({ node: dd.root.children[0] }).then(function () {
+                    cache = treeService._getTreeCache();    
+                });                
+            });
+
+            $rootScope.$digest();
+            $httpBackend.flush();
+
+            expect(cache.__content.root.children.length).toBe(4);
+            expect(cache.__content.root.children[0].children.length).toBe(4);
+            
+            treeService.clearCache({
+                cacheKey: "__content",
+                childrenOf: "1234"
+            });
+
+            cache = treeService._getTreeCache();
+
+            console.log(" blah: " + cache.__content.root.children.length);
+
+            expect(cache.__content.root.children.length).toBe(4);
+            expect(cache.__content.root.children[0].children).toBeNull();
+            expect(cache.__content.root.children[0].expanded).toBe(false);
+        });
 
     });