Question

I have one gsp file which calls a method like this:

<g:link id="${child.id}" action="callChildProfile" controller="profile">${child.firstname}</g:link>

which calls this method

    def callChildProfile(Long id){

           childInstance = Child.get(id)
           System.out.println(childInstance.firstname + "  child instance")
           redirect(action:  "index")

   }

this method set a child instance to a public variable called child instance but when the redirect happens the variable is reset.
The reason I redirect is because I want to load up the index page from this controller.

Index looks like this:

        def index() {
        def messages = currentUserTimeline()
        [profileMessages: messages]
         System.out.println(childInstance + " child here")
        [childInstance : childInstance]
    } 

Answer 1

Variables in controller methods (actions) have a local scope, thus, only can be used in that method. You should pass the id from new instance and use that id for retrieve the object.

redirect action: "index", id: childInstance.id

and index could be

def index(Long id){
    childInstance = Child.get(id)

Then you can conclude that you don’t need the callChildProfile method

or you can use params

def index(){
    childInstance = Child.get(params.id)
    if(childInstance){
        doSomething()
    }
    else{
        createOrGetOrDoSomethingElse()
    }
}