title: Grails controllers pass parameters
body: <p>My controller is the folowing:       </p>
  
  <pre><code>def participated = {
    def temp = ConferenceUser.get(params.temp)
  
    def prizes = Prizes.findAllByConferenceUser(temp) // find all rooms where current computer is
    def subms = Submissions.findAllByConferenceUser(temp) // find all rooms where current computer is
  
    [temp: temp, priz: prizes, subm: subms]
  }
  </code></pre>
  
  <p>But somehow, when I successfully update a conference value, I wanna go back to the initial page (participated) but I don't know how to pass back the <code>params.temp</code>. (if I do a simple redirect, as the controller is expecting <code>params.temp</code>, it will give me an error because I cannot search prizes with a null object as parameter. So, imagine my update controller is the following:</p>
  
  <pre><code>def update = {
    def saveParamshere = params.temp
    ...
    ...
    (code here)
    ...
    ...
  
    redirect(action: "participated", params: [temp: saveParamshere])
  }
  </code></pre>
  
  <p>This code isn't working. How can I successfully go back to my main page and pass in <code>params.temp</code> ?</p>