在Grails的自定义标记库中包含JQuery资源的正确方法

我正在为grails中的日期时间选择器制作一个自定义标记库。代码如下：

class jqueryDateTimePickerTagLib {

def dateTimePicker = {attrs, body ->
    def out = out
    def name = attrs.name    //The name attribute is required for the tag to work seamlessly with grails
    def id = attrs.id ?: name
    def value = attrs.value ?: new Date().format("yyyy/MM/dd HH:mm")


    //Create input data text field for contaning Date Time string
    out.println "<input type=\"text\" name=\"${name}\" id=\"${id}\" value=\"${value}\" ><img id=\"${id}opencalender\" src=\"${resource(dir:'images', file:'calendar_btn.png')}\"></input>"

    // Adding Resources
    out.println "<link rel=\"stylesheet\" href=\"${resource(dir:'css', file:'jquery.datetimepicker.css')}\" />"
    out.println "<script src=\"${resource(dir:'js/jquery', file:'jquery.js')}\"></script>"
    out.println "<script src=\"${resource(dir:'js/jquery/ui', file:'jquery.datetimepicker.js')}\"></script>"

    // java script code 
    out.println "<script>"
    out.println "\$('#${id}').datetimepicker({"

    out.println "});"
    out.println "\$('#${id}opencalender').click(function(){"
    out.println "\$('#${id}').datetimepicker('show');"
    out.println "});"

    out.println "</script>"
}
}

def resources = { attrs ->

    String style = attrs.style ? "${attrs.remove('style')}" : null;
    String theme = attrs.theme ? "css/${attrs.remove('theme')}.css" : "css/tiger.css";
    String lang = attrs.lang ? "calendar-${attrs.remove('lang')}.js" : "calendar-en.js";

    if(style) {
        out << "<style type='text/css'>@import url(${style});</style>"
    } else {
        out << "<style type='text/css'>@import url(${resource(dir:pluginContextPath,file:theme)});</style>"
    }

    out << """
            <script type="text/javascript" src="${resource(dir:pluginContextPath,file:"js/calendar.js")}"></script>\n
            <script type="text/javascript" src="${resource(dir:pluginContextPath,file:"js/lang/$lang")}"></script>\n
            <script type="text/javascript" src="${resource(dir:pluginContextPath,file:"js/calendar-setup.js")}"></script>\n

           """
}

class jqueryDateTimePickerTagLib{
def dateTimePicker={attrs，body->
def out=out
def name=attrs.name//name属性是标记与grails无缝工作所必需的
def id=attrs.id？：名称
def value=attrs.value？：新日期（）格式（“yyyy/MM/dd HH:MM”）
//为连续日期时间字符串创建输入数据文本字段
out.println“”
//增加资源
out.println“”
out.println“”
out.println“”
//java脚本代码
out.println“”
out.println“\$（'\${id}'）。日期时间选择器（{”
out.println“}”）
out.println“\$（'\${id}OpenCalendar'）。单击（函数（）{”
out.println“\$（'\${id}'）。日期时间选择器（'show'）；”
out.println“}”）
out.println“”
}
}

问题发生在我添加JQuery文件资源的地方。当此自定义日期时间选择器在GSP表单中包含两次时，会导致对每个包含多次声明JQuery资源。 我看到了一些标记库的示例，在这些标记库中，JQuery文件资源以不同的定义添加，如下所示：

class jqueryDateTimePickerTagLib {

def dateTimePicker = {attrs, body ->
    def out = out
    def name = attrs.name    //The name attribute is required for the tag to work seamlessly with grails
    def id = attrs.id ?: name
    def value = attrs.value ?: new Date().format("yyyy/MM/dd HH:mm")


    //Create input data text field for contaning Date Time string
    out.println "<input type=\"text\" name=\"${name}\" id=\"${id}\" value=\"${value}\" ><img id=\"${id}opencalender\" src=\"${resource(dir:'images', file:'calendar_btn.png')}\"></input>"

    // Adding Resources
    out.println "<link rel=\"stylesheet\" href=\"${resource(dir:'css', file:'jquery.datetimepicker.css')}\" />"
    out.println "<script src=\"${resource(dir:'js/jquery', file:'jquery.js')}\"></script>"
    out.println "<script src=\"${resource(dir:'js/jquery/ui', file:'jquery.datetimepicker.js')}\"></script>"

    // java script code 
    out.println "<script>"
    out.println "\$('#${id}').datetimepicker({"

    out.println "});"
    out.println "\$('#${id}opencalender').click(function(){"
    out.println "\$('#${id}').datetimepicker('show');"
    out.println "});"

    out.println "</script>"
}
}

def resources = { attrs ->

    String style = attrs.style ? "${attrs.remove('style')}" : null;
    String theme = attrs.theme ? "css/${attrs.remove('theme')}.css" : "css/tiger.css";
    String lang = attrs.lang ? "calendar-${attrs.remove('lang')}.js" : "calendar-en.js";

    if(style) {
        out << "<style type='text/css'>@import url(${style});</style>"
    } else {
        out << "<style type='text/css'>@import url(${resource(dir:pluginContextPath,file:theme)});</style>"
    }

    out << """
            <script type="text/javascript" src="${resource(dir:pluginContextPath,file:"js/calendar.js")}"></script>\n
            <script type="text/javascript" src="${resource(dir:pluginContextPath,file:"js/lang/$lang")}"></script>\n
            <script type="text/javascript" src="${resource(dir:pluginContextPath,file:"js/calendar-setup.js")}"></script>\n

           """
}

def资源={attrs->
字符串样式=attrs.style？”${attrs.remove（'style'）}）：null；
字符串theme=attrs.theme？“css/${attrs.remove（'theme'）}.css”：“css/tiger.css”；
字符串lang=attrs.lang？“calendar-${attrs.remove（'lang'）}.js”：“calendar en.js”；
如果（样式）{
out
def init={
out@moskiteau…即使应用了您的建议，JQuery文件也不会自动包含在我的GSP页面的标题中。