Custom Flow Transition?

[havvg]

I want to add a custom transition to a form flow. The one I currently require is very simple, but there might be more complex transitions. I'm not even sure, whether this is a good way to accomplish it. I got a flow, which got a step, that allows the user to choose whether to skip a defined part (multiple steps) of the flow.

Flow with custom transition:

class UpdateLeadFormFlow extends AbstractFormFlow
{
    const TRANSITION_SKIP_EDITOR = 'skip_editor';

    protected function loadStepsConfig()
    {
        $fnSkipEditor = function($step, UpdateLeadFormFlow $flow) {
            return UpdateLeadFormFlow::TRANSITION_SKIP_EDITOR === $flow->getRequestedTransition();
        };

        return [
            [
                // The first step, allowing to continue with 2nd or 5th step.
            ],
            [
                // ..
                'skip' => $fnSkipEditor,
            ],
            [
                // ..
                'skip' => $fnSkipEditor,
            ],
            [
                // ..
                'skip' => $fnSkipEditor,
            ],
            [
                // ..
            ],
        ];
    }

    // ...
}

The buttons.html.twig in use:

{% trans_default_domain "leads" %}

{% set prefix = 'update_lead.form_actions.step_' ~ flow.currentStepNumber ~ '.' %}

{% if flow.currentStepNumber == flow.firstStepNumber %}
    <button type="submit" class="btn btn-success btn-large pull-right" name="{{ flow.formTransitionKey }}" value="skip_editor">
        <i class="icon-circle-arrow-right"></i>&nbsp;
        {{- (prefix ~ 'skip')|trans -}}
    </button>
{% endif %}

<button type="submit" class="btn btn-success btn-large pull-right">
    <i class="icon-circle-arrow-right"></i>&nbsp;
    {{- (prefix ~ 'submit')|trans -}}
</button>

{% if flow.currentStepNumber in (flow.firstStepNumber + 1) .. flow.lastStepNumber %}
    <button type="submit" class="btn btn-large pull-right" name="{{ flow.formTransitionKey }}" value="back" formnovalidate>
        <i class="icon-circle-arrow-left"></i>&nbsp;
        {{- (prefix ~ 'back')|trans -}}
    </button>
{% endif %}

The thing I don't like is the unnecessary coupling customization of the template for the custom transition.

I would rather like to have a collection of transitions that are available on a given step. This collection contains the two default transitions already given reset and back. Each step may return a collection of additional transitions to be handled.

If a transition is active, the flow will handle it, e.g. by firing an event to delegate the changes in state. This would also allow to hook into resetting a flow or going backwards.

What are your thoughts? Am I missing some key elements to accomplish what I require? Are transitions the right way?

[lfjeff]

Would the ability to return to a specific step solve your problem?
take a look at issue #82

[craue]

Looks like this isn't easy to implement. I'd like to postpone it for a future version (if at all) in order to release 3.0.0 sometime soon.