Dynamic table driven menus

Question

Using jsf/adf bc I've been studying the 'dynamic' menu setup in the srdemo and have a decent understanding of how that works in a declarative way. However, that example assumes the menu items and their properties will be 'hard coded' into the faces-config. I have menu items and their properties (label, outcome, etc) stored in a table and I want to get rows from this table and essentially create an object of the MenuItem class for each row in the Menu table. I understand how to do this step programmatically. I'm left wondering then how to create the instance of MenuTreeModelAdapter and add each of these MenuItem instances to it and further how to create the instance of MenuModelAdapter and add the instance of MenuTreeModelAdapter to it?? Will this need to be a totally programmatic thing, or am i going to still be using some of the entries in the faces-config.xml? Thanks for any help on this.

Answer 1

John, thanks for the reply. I did search first and didn't come up with anything. I took a look at the example from the link you gave me. It didn't provide a lot of help, but I think I've got something I can use for my purposes. My application menu will have two levels, a menu and submenu. Therefore, there exists two db tables to hold info for each menu level. The submenu table rows are children of the menu rows and so are related by fk. In my application, I just created master/detail view objects and link to retrieve all menu items along with their submenu items. I then iterate thru the rows programmatically and populate the menu model that way. Initially, it seems to be working. I'll post that code in case it might help someone else:
public void buildMenuItems(){
ViewObjectImpl menuVO = getTopLevelMenu();
//iterate thru menu records
menuVO.executeQuery();
Row menuItemRow = null;
List menuItemsList = new ArrayList();
List submenuItemsList = new ArrayList();;
while(menuVO.hasNext()){
menuItemRow = menuVO.next();
//convert the menu row into an instance of a MenuItem object.
MenuItem menuItem = new MenuItem();
menuItem.setLabel((String)menuItemRow.getAttribute("MenuLabel"));
menuItem.setOutcome((String)menuItemRow.getAttribute("NavigationOutcome"));
menuItem.setViewId((String)menuItemRow.getAttribute("ViewId"));
RowSet sublevelMenuRows = (RowSet)menuItemRow.getAttribute("SublevelMenus");
while(sublevelMenuRows.hasNext()){
Row sublevelMenurow = sublevelMenuRows.next();
MenuItem sublevelMenuItem = new MenuItem();
sublevelMenuItem.setLabel((String)sublevelMenurow.getAttribute("SubmenuLabel"));
sublevelMenuItem.setOutcome((String)sublevelMenurow.getAttribute("NavigationOutcome"));
sublevelMenuItem.setViewId((String)sublevelMenurow.getAttribute("ViewId"));
submenuItemsList.add(sublevelMenuItem);
//if there were any sublevel menu items (children), add them to that menu item instance.
if(submenuItemsList.size() > 0){
//i'm basically making a copy of the submenu item list here so i can pass that to the setChildren method
//of the MenuItem object. Then i'm safe to clear() the original list so it can be used again. Without using
//a copy of the list to pass in, a subsequent call to clear() on that same list actually removes the children
//that were just placed into MenuItem from that object.
List submenuItemsListCopy = new ArrayList(submenuItemsList);
menuItem.setChildren(submenuItemsListCopy);
submenuItemsList.clear();
//add the MenuItem instance to a list.
menuItemsList.add(menuItem);
MenuTreeModelAdapter treeModelAdapter = new MenuTreeModelAdapter();
treeModelAdapter.setListInstance(menuItemsList);
treeModelAdapter.setChildProperty("children");
MenuModelAdapter modelAdapter = new MenuModelAdapter();
modelAdapter.setViewIdProperty("viewId");
try{
modelAdapter.setInstance(treeModelAdapter.getModel());
}catch(IntrospectionException ex){
//do nothing here...
FacesContext.getCurrentInstance().getExternalContext().getSessionMap().put("menuModel", modelAdapter);
}