如何将Javascript代码从Controller发送到GSP视图？

Question

I want to send some JS Script from controller to GSP view . I do the following attempt.

Controller(Purchase.groovy) :

 def myaction={
     flash.script= 'jQuery("div#header").show(1000);'
     redirect(action:'edit')
}

In purchase/myaction.gsp file, I try the following code

<g:if test="${flash.script !=null}">
    <g:javascript>
    $(function() {

            ${flash.script}
    })
   </g:javascript>
</g:if>
<g:else>
 <g:javascript>
    $(function() {

          alert('Welcome')
    })
   </g:javascript>
</g:else>

I try also : jQuery.getScript('${flash.script}') instead of '${flash.script}' However, GSP page renders always the second script(else statement)

Answer 1

First of all, be sure to call the function after the dom loaded; u can use jquery like

  $( document ).ready(function() {
     call_function();
  });

And you can send js code form controller as map, not through flash and redirecting to another action. See below:

 def myaction={
    redirect(action:'edit', customJs: 'jQuery("div#header").show(1000);')
 }

 def edit={
   render view: 'someView', model:[customJs: customJs]
}

And in view:

 <g:javascript>
$(function() {

        <%= customJs %>
})

Answer 2

flash.script is fine, I tested here and it works. What happens is that flash object is for transition, and will be available only in the next request. If your page is redirected to edit and you refresh edit , then flash will not be there anymore. Example:

• Go to myaction;
• Flow will redirect to edit;
• If you refresh the page, welcome will be printed.