Dynamically addFields(...) of LiftScreen by use ScreenVar failed in a loop.

[Sam]

val books: List[Book] = Books.all  //Book is MappedOneToMany Object

books match {

    case Nil => "was an empty list"

    case x :: xs => {

      object book extends ScreenVar(xs)

      addFields(() => book) // error: type mismatch;
//[INFO]  found   : book.type (with underlying type object up)
//[INFO]  required: net.liftweb.util.FieldContainer
//[INFO]       addFields(() => book)

    }

  }

[Sam]

Sorry, I have wrote wrong code for process the List.

Now the problem is solved:

  books.foreach(book => {

    object bFields extends ScreenVar(book)

    addFields(() => bFields)

  })

[Sam]

Encountered another problem:

  books.foreach(book => {

    object bFields extends ScreenVar(book)

    addFields(() => bFields)

  })

bFields is always the first book's fields of the books list.

For example, three books in books List, names are: A,B,C. But the bFields.name always is "A", therefore addFields had added three "A" in form.

I don't know how to do next...

Thanks for any help.

[David Pollak]

addFields is not meant to be used on each Wizard/Screen load.  It's called with a function that dynamically computes the fields.

So, if you want to list N books, you have to write a function that returns the FieldContainer that contains the fields for all the books you want to display.

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[Vladislav Dorokhin]

On Wednesday, May 9, 2012 6:17:50 PM UTC+2, Sam wrote:

Encountered another problem:

  books.foreach(book => {

    object bFields extends ScreenVar(book)

    addFields(() => bFields)

  })

  books map ( x => addFields( () => x.title ))