mongodb - 玩！框架 - 将多个列表返回到模板

Question

我有 3 个类，我想将 3 个列表返回到模板中，这些列表在我的数据库是 MongoDB 中使用

def addCourse = Action.async {implicit request =>
  val teacherCollection = db.collection[BSONCollection]("Teacher")
   val courseColl = subjectCollection.find(BSONDocument()).cursor[Subject].collect[List]()
   val teacherColl = teacherCollection.find(BSONDocument()).cursor[Teacher].collect[List]()

    courseColl.map { course =>
      val sam = teacherColl.map{teacher=>
        teacher
      }
    Ok(views.html.Course.addNewCourse(course,sam,Course.form))
   }
  }

模板代码：

   @(subject:List[models.Subject],teacher:List[models.Teacher],myForm: Form[models.Course])

我有一个错误：类型不匹配期望 List[Teacher] ，实际 Future[List[Teacher]]

我要做什么？

注意：如果我将 Ok(views...) 放入 val sam map，编译器会显示错误，这听起来像是异步错误，因为“异步”将是红色的

 Error:(59, -1) Play 2 Compiler: 
 /app/controllers/School.scala:59: type mismatch;
found   : Unit
  required: play.api.mvc.Result

Answer 1

我已经用 flatMap 解决了这个问题

courseColl.flatMap { course =>
  teacherColl.flatMap { teacher =>
    semesterColl.map { semester =>
      Ok(views.html.Course.addNewCourse(course, teacher, semester,    Course.form))
    }
  }
}