Grails render view of different controller

Question

My question is similar to this following post Render a view of another controller

I have a TestConfigController my question is what can I do in case validation fails and I want to render controller:test and view:edit rather then controller:testCOnfig and view:edit

def save() {

        def testConfigInstance = new TestConfig(params)
        if (!testConfigInstance.save(flush: true)) {

/*Rather then view:"edit" i want view:"/test/edit" which does not work */

            render(view:"edit",  model: [testConfigInstance: testConfigInstance],id:params.test.id)
            return
        }
        println "+++++++++++++++++++++++++"
        flash.message = message(code: 'Data successfully saved', args: [message(code: 'testConfig.label', default: 'Successfully saved')])
        redirect(action: "edit", controller:"test", id:params.test.id)
    }

Any pointers? I have already looked into grails redirect which does not have "model" param and thus can not pass the validation errors to the view Also I have looked in to grails render which does not have controller param so that I can go back to different controller! Please let me know if more detail/code is needed

EDIT Following happens while using one of the two things

render(view:"/test/edit",  model: [testConfigInstance: testConfigInstance],id:params['test.id'])

The code above renders the page /test/edit with no reference to testid eventually erroring out saying "test.id" can not be null.. (means its rendering /test/edit and not /test/edit/1)

render(view:"/test/edit/"+params['test.id'],  model: [testConfigInstance: testConfigInstance],id:params['test.id'])

The code above leads to following error

The requested resource (/EasyTha/WEB-INF/grails-app/views/test/edit/1.jsp) is not available.

Either one of the above code renders just "/test/edit" no id at the end, thus eventually erroring out saying test.id can not be null.

Solution 1

The value of id that you are trying to append in the view path should be a part of the model map. The values that you provide in the model map are available in the view that is rendered.

In the first option that you tried, the id parameter doesn't make any difference as the render method doesn't use any 'id' parameter (the redirect method uses the id parameter to generate the redirect url).

Your code snippet should be something like this:

render(view:"/test/edit",  model: [testConfigInstance: testConfigInstance, id:params['test.id']])

The render method that you are using here doesn't redirect you to some other action. render just prints the parsed viewName to the output stream. Eg. render(view:"/test/edit") just renders the edit.gsp view. It isn't actually redirecting you to the edit action of test controller. Therefore, just passing the id in the model map won't give you access to the testInstance on the view. You will have to get the testInstance By id and pass it to the view in the model map

render(view:"/test/edit",  model: [testConfigInstance: testConfigInstance, testInstance: Test.get(params['test.id'] as Long)])

Solution 2

Anuj Arora is right:

If you just want to render an arbitrary view you can use the full path to the view related to the grails-app/view folder:

In your case:

render(view:"/test/edit",  model: [testConfigInstance: testConfigInstance],id:params.test.id)

should work.

Solution 3

If you are only wanting to render the view /test/edit, then the call render(view:'/test/edit',...) should be all you need.

If instead, you also want to include some of the processing from the TestController and edit action, then look at the chain() call. It has a model parameter where you can pass the validation errors and controller/action parameters to redirect to the other controller.

Comments

[Anuj Arora]

The render closure with view "/test/edit" should be working. Which version of grails are you using?

[Jan Wikholm]

Could you provide more information on "does not work"? Do you get some error message? It should work.

[Sap]

@AnujArora Grails 2.0. It's now working but now thinking of it I have a feeling that it might not be working because of development context? May be I should try /context/test/edit

[Anuj Arora]

@Grrrrr You don't need to prepend the context on the view name. Grails should handle that.

[Sap]

@AnujArora sorry for a long absence, please see my edit

[Sap]

@JanWikholm sorry for a long absence, please see my edit

[Peter]

The con of the chain() call is that a redirect is sent to the client. This adds overhead to application. In this case I would prefer the include() call.

[schmolly159]

True, you could render the result of a g.include() call and save the redirect overhead. Had never considered that option.

[Sap]

Hey chain worked perfectly, still wondering how would include work in such a scenario where test has many testconfig and I am showing all testconfigs in test/edit/..

[schmolly159]

Since it is a Tag Library it is intended to be used in a GSP (for rendering templates instead of <g:render/>), but you can call them in a Controller, so you could try doing something like render(g.include(controller:'test',action:'edit',model:...))‌​.

[Sap]

This solution doesn't seem to be working the webpage renders with just test/edit and no reference to Id... my gut feeling is that it is due to the fact that model has testConfig instance while we are redirecting to test/edit?

[Anuj Arora]

The id should be available as a model parameter in the /test/edit view. Can you post your gsp here?

[Sap]

too big a GSP to paste here. if you don't mind can you download it? cynosuredev.com/edit.rar

[Anuj Arora]

@Grrrrr please see my edit. I think you are getting confused between redirect and render. This post might help you grails.1312388.n4.nabble.com/…

[Sap]

Thanks a lot, this works. I understand that render is equivalent to forward in java while redirect is to redirect:) Anyways, thanks a lot for your help it never occurred to me that I can send two objects in a model.