I know this is old, but for posterity. The MenuItem Class has methods for configuring this.

        //
    // Summary:
    //     Sets the menu item to display a dialog based on a url path in an iframe
    //
    // Parameters:
    //   url:
    //
    //   dialogTitle:
    public void LaunchDialogUrl(string url, string dialogTitle);
    //
    // Summary:
    //     Sets the menu item to display a dialog based on an angular view path
    //
    // Parameters:
    //   view:
    //
    //   dialogTitle:
    public void LaunchDialogView(string view, string dialogTitle);
    //
    // Summary:
    //     Sets the menu item to navigate to the specified angular route path
    //
    // Parameters:
    //   route:
    public void NavigateToRoute(string route);

On top of the MenuItem class... There is what I consider a better way in Umbraco 7.

ActionMenuItem and ActionMenuItemAttribute.

Basically, create a class for your menu item and derive from ActionMenuItem.

In the constructor set the alias for the menu item, whether to have a separator, etc.

Than decorate it with the ActionMenuItemAttribute class, E.g.

[ActionMenuItem("tlckbMenuActions", "HelloWorld")]
public class EditContentPermissionAction : ActionMenuItem
{
    private TLCKBNodeType nodeType = TLCKBNodeType.Root;

    public EditContentPermissionAction(TLCKBNodeType nodeType)
    {
        this.nodeType = nodeType;
        this.Alias = "tlckb_EditNodePermissions_" + nodeType.ToString();
        this.Icon = "icon-lock";
        this.Name = "KB Permissions";
        this.SeperatorBefore = true;
    }
}

Now in your menu rendering code, you can attach that ActionMenuItem to any TreeController and or specific menu node.

For example, here's mine,

    //Add the KB Edit Content Permission Menu Items to the Content Menu.  Only add the menu item to the content menu if the node being explored
    //is a KB Root Node, KB Category Node, or KB Article Node.
    void TreeControllerBase_MenuRendering(TreeControllerBase sender, MenuRenderingEventArgs e)
    {
        string treeAlias = sender.TreeAlias; string nodeId = e.NodeId;
        if (string.IsNullOrEmpty(treeAlias))
            treeAlias = e.QueryStrings.Get("TreeType");
        if (string.IsNullOrEmpty(treeAlias) || nodeId == "-1")
            return; 
        //get the content of the clicked on node to get it's content type
        var currentNode = ApplicationContext.Current.Services.ContentService.GetById(Convert.ToInt32(e.NodeId));
        string contentType = currentNode != null ? currentNode.ContentType.Alias : string.Empty;
        switch (treeAlias)
        {
            case "content": //the clicked on node is in the content tree, this is the section we are interested in
                //now determine if the clicked on node is a KB node, if so, add the menu item for that node.  We have 3 different views for permissions of the different node types.
                if (contentType == KBApplicationCore.KBRootContentType.Alias)
                    e.Menu.Items.Add(KBMenuItems.RootEditPermissionAction);
                if (contentType == KBApplicationCore.KBCategoryContentType.Alias)
                    e.Menu.Items.Add(KBMenuItems.CategoryEditPermissionAction);
                if (contentType == KBApplicationCore.KBArticleContentType.Alias)
                    e.Menu.Items.Add(KBMenuItems.ArticleEditPermissionAction); 
                    break;
            default:
                break;
        }
    }

That adds my Action to the menu of any node that is based on 1 of three content types and only in the content tree controller.

So my action only shows up when users are looking at content for the Knowledge Base.

Now, the attribute specific a service and a method name. This needs to be an angular service defined in the umbraco module. And the method name is a method on said service.

Umbraco has one already called umbracoMenuActions. You might be able to leverage the out of the box service to do things.

However for me, I needed a custom menu action service.

So I create a fodler for my knowledge base in App_Plugins and gave it a sub folder called XYZPlugin (change name).

In there I created a package manifest and added my custom javascript to it.

{
   javascript: [
       '/App_Plugins/XYZPlugin/backoffice/js/services/menuItems.js'
   ]
}

Then you just need to define your service in menuItems.js

angular.module("umbraco").factory('xyzMenuActions', ['$http', '$q', 'treeService', '$location', 'navigationService', 'appState', function ($http, $q, treeService, $location, navigationService, appState) {
    var factory = new function () {
        this.HelloWorld = function () {
            alert('Hello!!! From menuActions Service!');
        }
    };
    return factory;
}]);

I copied the service dependencies from umbraco's out of the box menuAction service which is located in /umbraco/js/umbraco.services.js

All said and done, when I click on a KB specific node in the content tree and go to "Do Something Else" I see "KB Permissions" and when I click it

"Hello!!! From menuActions Service!"

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