grails ajax分页标签实现

grails ajax分页标签实现
一、设计目标
1、采用ajax实现
2、要多少条数据，取多少条，不从数据库中一次性全部取出
3、实现指定页面跳转
4、用户可以指定选择每页显示几条数据
5、按那个字段排序
6、最好不要占用session
二、如何实现
2、传入参数：显示页码，共有多少条数据，每页显示几条数据,返回的页面
       可选按那个字段排序

        if(!params.total){
            params.total=TestAjaxPage.count()///这个必须要，ajax请求时就不用在count总数了
        }
        params.view=params.view==null?"list":params.view
        params.max = Math.min(params.max ? params.max as int : 2, 100)
        params.linkTotal = Math.min(params.linkTotal ? params.linkTotal as int : 2, 100)
        params.offset = Math.min(params.offset ? params.offset as int : 0, 100)
        params.sort=params.sort==null?"dateCreated":params.sort
        params.order=params.order==null?"desc":params.order
截个图：

talib code
import org.springframework.web.servlet.support.RequestContextUtils as RCU;
import org.codehaus.groovy.grails.commons.ConfigurationHolder
class AjaxPageTagLib {
    def paginateAjax={attrs ->
        def writer = out
        params.offset = Math.min(params.offset ? params.offset as int : 0, 100)
        params.sort=params.sort==null?"dateCreated":params.sort
        params.order=params.order==null?"desc":params.order
        def messageSource = grailsAttributes.getApplicationContext().getBean("messageSource")
        def locale = RCU.getLocale(request)       
        def total = attrs.total.toInteger()
        def offset = params.offset?.toInteger()
        def max = params.max?.toInteger()
        int pageSize=Math.round(Math.ceil(total / max))   
        def path=request.getContextPath()   
        def pageNow=offset/max+1
        def selectMax=attrs.selectMax?.toInteger()
        if(!selectMax){
            selectMax=20
        }
        selectMax=selectMax>total?total:selectMax
        ////js输出
        writer<<"""
         <div id="ajaxPage">
        """
        /////显示首页和上页
        def firstText=messageSource.getMessage('paginate.first', null, messageSource.getMessage('default.paginate.first', null, 'First', locale), locale)
        def prevText=messageSource.getMessage('paginate.prev', null, messageSource.getMessage('default.paginate.prev', null, 'Prev', locale), locale)
        def nextText=messageSource.getMessage('paginate.next', null, messageSource.getMessage('default.paginate.next', null, 'Next', locale), locale)
        def lastText=messageSource.getMessage('paginate.last', null, messageSource.getMessage('default.paginate.last', null, 'Last', locale), locale)
       
        if(offset!=0){
            def firstUrl="""offset=0&max=${params.max}&sort=${params.sort}&order=${params.order}&total=${total}"""
            writer<<"""
            <span id="firstShow" title="${firstText}" onclick="new Ajax.Updater('${attrs.update}',
        '${path}/${params.controller}/${params.action}',{asynchronous:true,evalScripts:true,parameters:'${firstUrl}'});
        return false;" >
            [${firstText}]
            </span>
            """
            int prev=offset-max
            def prevUrl="""offset=${prev}&max=${params.max}&sort=${params.sort}&order=${params.order}&total=${total}"""
            writer<<"""
                <span id="preShow" title="${prevText}" onclick="new Ajax.Updater('${attrs.update}',
            '${path}/${params.controller}/${params.action}',{asynchronous:true,evalScripts:true,parameters:'${prevUrl}'});
            return false;" >
                [${prevText}]
                </span>
                """
        }
        else{
            writer<<"""<span id="firstNoShow" title="${firstText}">
                      [${firstText}]
                      </span>
                """
            writer<<"""<span id="preNoShow" title="${prevText}">
                    [${prevText}]
                    </span>
                    """
        }
        ////数据信息输出
        writer<<"""<span id="ajaxPageInfo">当前${pageNow}/${pageSize}页（共${total}）</span>"""
       
        //下一页和末页输出，
        if(offset!=max*(pageSize-1)){
            int next1=offset+max
            def nextUrl="""offset=${next1}&max=${params.max}&sort=${params.sort}&order=${params.order}&total=${total}"""
           
            writer<<"""
                <span id="nextShow"   title="${nextText}" onclick="new Ajax.Updater('${attrs.update}',
            '${path}/${params.controller}/${params.action}',{asynchronous:true,evalScripts:true,parameters:'${nextUrl}'});
            return false;" >
                [${nextText}]
                </span>
                """
            int last=max*(pageSize-1)
            def lastUrl="""offset=${last}&max=${params.max}&sort=${params.sort}&order=${params.order}&total=${total}"""
            writer<<"""
                <span id="lastShow" title="${lastText}" onclick="new Ajax.Updater('${attrs.update}',
            '${path}/${params.controller}/${params.action}',{asynchronous:true,evalScripts:true,parameters:'${lastUrl}'});
            return false;" >
                [${lastText}]
                </span>
                """
        }
        else{
            writer<<"""<span id="nextNoShow" title="${nextText}">
                [${nextText}]
                </span>
                """
            writer<<"""<span id="lastNoShow" title="${lastText}">
                [${lastText}]
                </span>
                """
        }
        ///到指定页连接输出
        def selectUrl="&max=${params.max}&sort=${params.sort}&order=${params.order}&total=${total}"
        writer<<"""
        <span id="ajaxSelectText">转到<select id="ajaxSelect" onchange="myUpdate('${attrs.update}','${path}/${params.controller}/${params.action}'
        ,'${selectUrl}','${max}')">
       
        """
        for(int j=1;j<=pageSize;j++){
            if(pageNow!=j){
                writer<<"""  <option value ="${j}">${j}/${pageSize}</option>           """
            }
            else{
                writer<<"""  <option value ="${j}"  selected="selected">${j}/${pageSize}</option>           """
            }
        }
        writer<<"</select>页</span>"
       
        ////每页显示几条数据
        def maxUrl="&offset=0&sort=${params.sort}&order=${params.order}&total=${total}"
        writer<<"""
             <span id="ajaxMaxText"> 每页显示</span><select id="ajaxMax" onchange="myUpdate2('${attrs.update}','${path}/${params.controller}/${params.action}'
            ,'${maxUrl}')">
            """
        for(int j=1;j<=selectMax;j++){
            if(max!=j){
                writer<<"""<option value ="${j}">${j}</option>"""
            }
            else{
                writer<<"""<option value ="${j}"  selected="selected">${j}</option>"""
            }
        }
        writer<<"</select> </div>"
    }
}
example code

        if(!params.total){
            params.total=CompanyFinance.count()////注意total参数
        }
        def hql="select id,title,dateCreated from CompanyFinance "
        params.view=params.view==null?"list":params.view
        params.max = Math.min(params.max ? params.max as int : 2, 100)
        params.linkTotal = Math.min(params.linkTotal ? params.linkTotal as int : 2, 100)
        params.offset = Math.min(params.offset ? params.offset as int : 0, 100)
        params.sort=params.sort==null?"dateCreated":params.sort
        params.order=params.order==null?"desc":params.order
        params.selectMax="true"///暂时没用
        def results = sessionFactory.currentSession.createQuery(hql+" order by ${params.sort} ${params.order}")
           .setCacheable(false)
           .setReadOnly(true)
           .setFirstResult(params.offset)
           .setMaxResults(params.max)
           .list()
   
        render view:params.view,model:[pageAjaxList:results,paginateAjaxTotal:params.total]<g:paginateAjax total="${paginateAjaxTotal}" update="update1"
    selectMax="20" />
对了，还有js,css
function myUpdate(update1, url1, parameters1, max) {
    var selectValue = document.getElementById("ajaxSelect").value
    var offset = max * (selectValue - 1)
    var newParams = "offset=" + offset + parameters1
    new Ajax.Updater(update1, url1, {
        asynchronous : true,
        evalScripts : true,
        parameters : newParams
    });
    return false;
}
function myUpdate2(update1, url1, parameters1) {
    var max = document.getElementById("ajaxMax").value
    var newParams = "max=" + max + parameters1
    new Ajax.Updater(update1, url1, {
        asynchronous : true,
        evalScripts : true,
        parameters : newParams
    });
    return false;
}
css:(css水平有限啊)，table的css最好自己写，如果 用默认的main.css会报错

@CHARSET "UTF-8";
#firstShow{
  color:#0000cc;
  cursor:hand;
  cursor:pointer;
}

#preShow{
  color:#0000cc;
  cursor:hand;
  cursor:pointer;
}
#ajaxPageInfo{
  color:#000000;
}

#nextShow{
  color:#0000cc;
  cursor:hand;
  cursor:pointer;
}
#lastShow{
  color:#0000cc;
  cursor:hand;
  cursor:pointer;
}


#ajaxSelectText{
   color:#000000;
}

#ajaxMaxText{
   color:#000000;
}
#firstNoShow{
}

#preNoShow{

}

#nextNoShow{
}

#lastNoShow{
}grails 1.1
grails 1.3.5下测试通过
最后页面上应该以下几句
<g:javascript library="prototype" />
<script type="text/javascript" src="${resource(dir: 'js', file: 'ajaxPage.js')}"></script>
<link rel="stylesheet" href="${resource(dir:'css',file:'ajaxPage.css')}" />
要源码可以下载：

hg clone https://[email protected]/asdtiang/mygrailsstudy