grails - Grails中的两个排序规则

Question

使用以下代码:

<g:each in="${books.sort{it.date}}" status="i" var="book"> 
    ${book}
</g:each>

我想显示按日期排序的书；另外，我希望首先显示当前登录者创作的书籍。

那可能吗？

Answer 1

不确定要达到的目标，但是可以做到这一点。在将books列表传递到GSP之前，您可以这样编写:

def myAction() {
     List books = Book.list()  // Get your book list

     User loggedInUser = User.first()  // Get your currently logged in user

     // First get all the books of current user sorted by the date
     List currentUsersBooks = books.findAll { it.author.id == loggedInUser.id }.sort{ it.date }

     // Then get other books sorted by date
     List otherBooks = books.findAll { it.author.id != loggedInUser.id }.sort{ it.date }

     // Now merge all of them (as `List` will maintain insertion order)
     // So current user's book will be listed first and then others
     List allBooks = currentUsersBooks + otherBooks

     [books: allBooks]
}

现在，修改您的GSP，使其不再进行排序:

<g:each in="${books}" status="i" var="book"> 
   ${book}
</g:each>

考虑到 Book和 User域类是这样的:

class User {
     String email
}

class Book {
     Strig title
     User author
}