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grailsgroovygrails-pluginspring-webflow

Grails SubFlow doen't render its view page and returns HTTP 404

I am using Grails 2.3.6 with the WebFlow 2.0.8.1 plugin installed. I am trying to get a proof-of-concept working with a SubFlow. After reviewing the example SubFlow documented here, I am having difficulty getting a simple SubFlow to work.

Note: I am a new comer to Grails and WebFlow in general.

This is my project structure:

Project Structure

HelloController renders this page:

HelloController Page

DemoController renders this page:

DemoController Page

However, when I click the Go To Sub Flow button on the HelloController's page, I get a 404:

enter image description here

If I supply /hello/hello/subflowDemo.gsp, the page renders but it is not the page from DemoController.

What am I doing wrong?

HelloController:

package helloworld

class HelloController {
    def helloFlow = {
        hello {
            on("goToSub").to "subflowDemo"
        }
        subflowDemo {
            subflow(controller: "demo", action: "demo")
        }
    }
}

hello.gsp:

<html>
<body>
    Hello world!
    <g:form>
        <g:submitButton name="goToSub" value="Go To Sub Flow" />
    </g:form>
</body>
</html>

DemoController:

package helloworld

class DemoController {
    def demoFlow = {
        demo {
        }
    }
}

demo.gsp:

<html>
<body>
    This is the demo screen!
</body>
</html>
Solution

  • You have to complete the Flow Cycle. I believe subflow's state cannot be the end state for the Main flow. So End the flow in the main flow.

    The following code changes worked for me,

    HelloController.groovy

    class HelloController {

    def helloFlow = {
        hello {
            on("goToSub").to "subflowDemo"
        }
        subflowDemo {
            subflow(controller: "demo", action: "demo")
            on("gotomainflow").to "endstate" // have a transition to endstate

        }
        endstate {

        }
    }

}

    endstate.gsp in views/hello/hello/endstate.gsp

    <html>
<body>
    Came Back to main- endstate
</body>
</html>

    DemoController.groovy

    class DemoController {
    def demoFlow = {
        demo {
            on("gotomainflow").to "gotomainflow" //have the transition which calls a event
        }
        gotomainflow() // this event will trigger the event in the main flow
    }
}

    demo.gsp in views/demo/demo/

    <html>
<body>
    This is the demo screen!
    <g:form>
        <g:submitButton name="gotomainflow" value="Go To Main Flow" />
    </g:form>
</body>
</html>