Grails 分页无法正常工作

Question

我是 Grails 的新手，我尝试使用文档中的分页标签来显示特定数据。

分页显示在我的页面上，但是当我滑过它们时，它会在每个页面上显示我的所有数据，我希望每页仅显示总和中的 10 个项目。

这是我的控制器

class HomeController {

    def actions() {
       params.max = Math.min(params.max ? params.int('max') : 10, 100)

       def articleActionOpera = newSuggestedShoppingItemsService.getNewSuggestedShoppingItems()

       return [articles: articleActionOpera, actionTotal: articleActionOpera.size(), params:params]
    }
}

这是我的服务

class NewSuggestedShoppingItemsService {

   def operaOpusDbConnectorService

   def getNewSuggestedShoppingItems() {

      def returnRows = null
      def sqlInstance = operaOpusDbConnectorService.openOperaOpusConnection()

      try {
         def sqlQuery = "SELECT passW, ArtName, Descript FROM dbo.fnWS_Newarticles()"

         returnRows = sqlInstance.rows(sqlQuery)

         return returnRows
      }
      catch(Exception ex) {
         log.error("Fail, item are not shown.")
         throw new Exception (ex)
      }
   }
}

还有我的 .gsp

...

<div id="paging">
   <g:paginate total="${actionTotal}" />
</div>

Answer 1

您实际上并没有将任何分页参数（最大和偏移量）传递给您的数据库查询，从而获取所有记录。因此，将它们传递给您的查询，这将起作用。

第二件事，您将总计数作为返回结果的大小（其中值正确但编程错误）和最大/偏移量传递给 Grails 分页指令，即为什么它呈现正确的分页 HTML sn-p。

例子：

class HomeController {

    def actions(Integer max) {
       params.max = Math.min(max ?: 10, 100)

       List articleActionOpera = newSuggestedShoppingItemsService.getNewSuggestedShoppingItems()

       // You don't have to pass params in model, it is bydefault available in GSPs
       return [articles: articleActionOpera, actionTotal: articleActionOpera.totalCount]
    }
}

服务：

class NewSuggestedShoppingItemsService {

   List getNewSuggestedShoppingItems(Map params) {
      // Consider ShoppingItem is a domain class and params is containing max & 
      // offset parameters then it will return an instance of PagedResultList (List)
      // which will have a totalCount field

      List shoppingItems = ShoppingItem.createCriteria().list(params) {
           // Your criteria
           eq("status", "ACTIVE")
      }


      return shoppingItems
   }
}

在此处阅读更多信息http://grails.github.io/grails-doc/latest/ref/Domain%20Classes/createCriteria.html

Answer 2

嗨，Damir 使用下面的说明，您将很容易在 grails 中实现分页：

查看您的代码是可以的：（无需更改）

<div id="paging">
   <g:paginate total="${actionTotal}" />
</div>

在控制器中：

class HomeController {

    def actions(Integer max) {
       params.max = Math.min(max ?: 10, 100)
//change here
       List articleActionOpera = newSuggestedShoppingItemsService.getNewSuggestedShoppingItems(params)

       // You don't have to pass params in model, it is bydefault available in GSPs
       return [articles: articleActionOpera, actionTotal: articleActionOpera.totalCount,params:params]
    }
}

在服务中使用创建标准：

class NewSuggestedShoppingItemsService {

   def operaOpusDbConnectorService

   def getNewSuggestedShoppingItems(def params) {

      def returnRows = null
   /*   def sqlInstance = operaOpusDbConnectorService.openOperaOpusConnection()

      try {
         def sqlQuery = "SELECT passW, ArtName, Descript FROM dbo.fnWS_Newarticles()"

         returnRows = sqlInstance.rows(sqlQuery)

         return returnRows
      }
      catch(Exception ex) {
         log.error("Fail, item are not shown.")
         throw new Exception (ex)
      }*/

returnRows=YourDomainName.createCriteria().list(params) {
 projections {
        property("passW")
        property("ArtName")
        property("Descript")
    }
}

   }
}

注意：必须更改 YourDomainName == 映射到表的类的名称 它会正常工作。