What do you think is the best way to present a hierarchical list of functionality to users within your traditional WinForms application? (A menu system - Assume functionality can be split into a small number of modules and sub-modules but with no fixed depth in terms of those sub-modules).
Do you like the traditional drop down menu system, ribbons, docked toolbars, a treeview approach or any other innovative ideas?
You could always opt for the increasingly ribbon control. Microsoft/Office interfaces have a habit of becoming the user's expectation of norm (eventually).
I often have a toolstrip docked on top for those functions that is most used. And all other as drop down menues with hotkeys set.
If I have a list that can contain different types of items I use a bottom docked toolstrip that change its content depending on the selected item in the list. That way I only have buttons/icons that is relevant for the task and not a bunch of disabled buttons irritating the view.
I also add a context menu for the items that automagically fills with the same choises as the bottom toolstrip. That way I give a faster way to get to the "action" without having to move the mouse down to the bottom of the screen.
I really hate the ribbon-thing (as a user) so I dont use it as a programmer in my projects.
In my opinion there is no definite answer to your question. It always depends on the menu you are presenting to the user and the users that are expected to use the application
A menu with standard/common functionalities is probably best presented Office style meaning drop down menus or the newly Ribbon style. A menu with custom functionality and, as you state multiple modules and submodules with different depths, is often best presented as a TreeView-like menu.
Looking from the point of the user, a typical user will do just fine with a standard menu whereas a more advanced user won't mind more advanced features like keyboard navigation or possibility to hide/show the menu or dock it to the other side of the window.
In my opinion the best way is to make sure everything can be done in several ways.
So the user can choose it's way around.
What I really like to see in more application is that a menu or option is directly attached to the selected item (control) a user is looking at. And of course the menu is in context with the given content.
I have implemented this in my open source project Monex and I really like using it myself. Just look at this screenshot.
An important thing to consider in your design is Usability vs Discoverability.
The best solution depends strongly on who you users are. The UI requirements for a kiosk application for tourists in a city centre are very different to those for a control screen at a power station...
Menubars, toolbars, and Ribbons are used for commands, where the user selection of an item acts on a data object displayed in the window or the application as a whole. Which one you use depends primarily on the number of commands in your app.
Toolbar alone: About 20 or fewer commands. Provide both icons and text labels for each command button. Represent the hierarchy by separators. Have no more than two levels –flatten your hierarchy accordingly.
Menubar with toolbar: Over about 20 but less than about 1000 commands. Up to twenty menu items on a single menu (using separators) is generally better than cascade menus –flatten your hierarchy accordingly. Common commands should have accelerators. Generally limit your toolbar to no more than 30 of the most commonly used commands, primarily commands otherwise only accessible from within a dialog box. Consider not having toolbar controls for menu items that have accelerators –one good means of expert access is often sufficient.
Ribbon: Over 1000 commands. A Ribbon is little more than putting different menubars-and-toolbars on separate tabs. To work well, the tasks associated with each tab (the top of your function hierarchy) should be non-integrated –users relatively rarely switch from one to the other. The Ribbon is also tends to be more effective for promoting discovery of advanced features at the price of discoverability and efficiency of basic features.
Check if items in your function hierarchy may be better represented as attributes rather than commands. Commands carry out a process, such as Open, Find, and Copy, while attributes change specific characteristics of something, such as Font, Size, and angle of view. Attributes are set by field controls within your window (e.g., text boxes, check boxes, and dropdown lists) rather than menu items, toolbar controls, or Ribbon controls.
A window-full of such field controls (or other representations of data objects) is a content block. Tree controls may be used to control what content block is shown. Like tab controls, they are preferred over multiple windows when the user frequently switches among the content blocks and does not compare content blocks. Trees are preferred over tab controls when the amount of content will not fit in a single row of tabs.
Do not have any empty nodes in your tree. Anything the user clicks on should display a full pane of content –flatten your hierarchy accordingly, even going to the extreme of using a list box rather than a tree.
If users tend to select one content block, complete a task there, then leave your app, then consider a “home” page displaying a full-page menu of all the content blocks, possibly spatially arrange according to your hierarchy, each accessible with a single click.