Correction: ModelSnippet.load takes the actual Mapper instance, not the ModelView wrapper.
------------------------------------- Naftoli Gugenheim<[email protected]> wrote: To answer your immediate question, the listing should not refer to the snippet's view but new ModelView instances for each entity. Then editAction is shorthand for the snippet's link method with a callback to call load on the ModelView. To set the snippet's view's entity, either call load on the snippet with the other ModelView, or call load on the other ModelView (or just set its entity directly). As far as documentation, please tell me what scaladocs need what clarification. Thanks. ------------------------------------- glenn<[email protected]> wrote: 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 <[email protected]> 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<[email protected]> 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 <[email protected]> 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 <[email protected]> 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 > > > <[email protected]>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<[email protected]> 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 <[email protected]> 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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