Naftoli, Functional programming systems are notoriously difficult to document. The only way to really know what's going on is to meticulously trace through the source. But that requires time-consuming trial and error coding. So, without clear examples demonstrating exactly what you have in mind, I and others in the same boat, could spend days and still not get it right.
For example, I tried this: var theUser:User = null val view = new ModelView(theUser, this) def list(ns: NodeSeq): NodeSeq = User.currentUser.map({user => User.findAll.flatMap({u => bind("user", chooseTemplate("user", "entry", ns), "firstname" -> Text(u.firstName.is), "lastname" -> Text(u.lastName.is), "email" -> Text(u.email.is), "roles" -> u.roles.map(_.name.toString).mkString(", "), view.editAction, view.removeAction ) }) }) openOr Text("You're not logged in") and, I get a null value exception when I try to remove a user in the list. Simply using val view = new ModelView(new User, this), doesn't work either, although I don't get an exception. Now, where should I be calling load in all of this? Glenn... On Aug 3, 6:22 pm, Naftoli Gugenheim <naftoli...@gmail.com> wrote: > Your snippet should extend ModelSnippet (which extends StatefulSnippet). > Then write: > val view = new ModelView(new User, this) {} > Calling load on another ModelView that references the snippet will load its > entity into that view val. It has a number of methods of possible interest, > like save which checks validity. > Also see Util. > Are you seeing the scaladocs? > > ------------------------------------- > > glenn<gl...@exmbly.com> wrote: > > Just to add to what I just wrote, I don't see how your ModelView can > be applied to > User, which already extends a class, MegaProtoUser. Maybe I'm not > comprehending this correctly. > > Glenn... > > On Aug 3, 3:48 pm, glenn <gl...@exmbly.com> wrote: > > > Naftoli, > > > Liked your OneToMany article, but not sure how the new > > ModelView and ModelSnippet code can be applied to ManyToMany. > > Can you provide a sample? > > > Glenn... > > > On Aug 2, 1:21 pm, Naftoli Gugenheim <naftoli...@gmail.com> wrote: > > > > I put an article on the wiki about OneToMany > > > --http://wiki.github.com/dpp/liftweb/how-to-work-with-one-to-many-relat... > > > . > > > > On Sun, Aug 2, 2009 at 11:20 AM, Naftoli Gugenheim > > > <naftoli...@gmail.com>wrote: > > > > > Glad to hear. Also see mapper.view.ItemsList (anyone have a better > > > > name?), > > > > which is used by TableEditor. It's a similar idea without relationships. > > > > Should MappedOne/ManyToMany be based on ItemsList? > > > > Also should I take Mapped out of those names? After all, they're not > > > > MappedFields and they don't correspond to a table column. > > > > > ------------------------------------- > > > > Magnus Alvestad<magnus.alves...@gmail.com> wrote: > > > > > This work that you've done in Mapper fits in very well with something > > > > I've been planning to do. In a Java project some time ago we > > > > implemented a 'change engine'. We were loading big pension agreements, > > > > manipulating them in a web interface and finally saving them back to > > > > the database. While the user was working on the agreement, we > > > > generated a list of changes, containing enough information to replay > > > > or unroll the change. We could use this to implement undo and some > > > > semi-intelligent merging when two users were trying to commit changes > > > > to the same agreement. We also let the user review his changes before > > > > saving, and we indicated changed fields visually. We were even > > > > thinking of implementing some kind of macro or replay functionality, > > > > but never got that far. > > > > > I've been trying to implement something similar as a lift component, > > > > but with the old relationship handling it wasn't practical. With your > > > > changes it should be. Thanks! > > > > > -Magnus > > > > > On Jul 27, 9:57 pm, Naftoli Gugenheim <naftoli...@gmail.com> wrote: > > > > > I committed some code last night, which can help building mapper-based > > > > view snippets, with G-d's help. It includes the following classes: > > > > > (1-2) net.liftweb.mapper.OneToMany, ManyToMany: Gives a more > > > > object-oriented approach to managing related entites. You can manage the > > > > many side of a 1-n and n-n as a mutable collection of children, and the > > > > parent of a child can be set directly, instead of via its id. And the > > > > children are not saved to the database when you add them until you call > > > > save > > > > on it or its parent, nor deleted when you remove tem until you call > > > > delete_!, which is very helpful when you need to keep track of > > > > adds/removes > > > > through multiple requests. For example, if you are displaying a list > > > > and you > > > > can click delete, but it shouldn't be permanently deleted until you > > > > click > > > > save. > > > > > There is a new package, ...mapper.view, which contains a number of > > > > utilities for mapper-based views: > > > > > (3-4) ModelView and ModelSnippet provide a number of building blocks > > > > > for > > > > views that are too complex to CRUDify. Inherit ModelSnippet (which > > > > extends > > > > StatefulSnippet) and wrap your entities in ModelView (view is used in > > > > the > > > > sense of a wrapper). > > > > > (5) Util provides some more building blocks that just be imported, > > > > without needing a ModelSnippet context. > > > > > (6-7) Paginator makes it easy to create paginated, user sortable > > > > listings. You can use PaginatedSnippet instead of ModelSnippet to help. > > > > > (8-10) ItemsList lets you manage a list of entities with pending > > > > additions and deletions. It's used by TableEditor, which is a very easy > > > > to > > > > use and customizable snippet to edit tables directly. It's useful for > > > > editing short lists, e.g., a lookup table like cities. Don't forget to > > > > register the table in Boot. > > > > > (11) Then there's the experimental FormProcessor, if you need your > > > > > form > > > > to be processed in one block instead of separate closures, e.g., to > > > > surround > > > > with try. > > > > > (12) Also experimental is sitemap.XmlMenu which lets you write menus > > > > > in > > > > xml. > > > > > (13) I may add CaseEnum, which lets you write case classes that > > > > automatically double as an Enumeration. > > > > > Questions, comments, suggestions, and constructive criticism are more > > > > than welcome! > > > > > Thanks. --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Lift" group. 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