Step 3: Grouping Transitions and Adding Conditions to Transitions

In this step, you will group transitions and add a condition to each transition.

To specify the conditions you defined in Step 1: Adding a Condition of this activity, do the following:

1. In the lambda expression provided for the WithTransitions method, define a group of transitions, as the following code shows.

                       .WithTransitions(transitions =>
                       {
                           transitions.AddGroupFrom<States.onHold>(transitionGroup =>
                           {
                           });
                       })

   In the code above, you have defined a group of transitions whose initial workflow state is OnHold.

2. Move the definition of the transition that you added in Transitions: To Implement a Transition Triggered by an Action inside the group, and remove the call of the From method because it is no longer necessary. The resulting code is shown below.

                           transitions.AddGroupFrom<States.onHold>(transitionGroup =>
                           {
                               transitionGroup.Add(transition => 
                                   transition.To<States.readyForAssignment>()
                                   .IsTriggeredOn(graph => graph.ReleaseFromHold)
                               );
                           });

3. After the IsTriggeredOn method call, add the When method call, and specify the RequiresPrepayment condition with the logical NOT operator, as the following code shows.

                                   transition.To<States.readyForAssignment>()
                                   .IsTriggeredOn(graph => graph.ReleaseFromHold)
                                   .When(!conditions.RequiresPrepayment));

4. After this transition, add the new transition from the OnHold state to the PendingPayment state, as the following code shows. Specify the RequiresPrepayment condition.

                               transitionGroup.Add(transition => 
                                   transition.To<States.pendingPayment>()
                                   .IsTriggeredOn(graph => graph.ReleaseFromHold)
                                   .When(conditions.RequiresPrepayment));

5. Save your changes.

                    .WithTransitions(transitions =>
                    {
                        transitions.AddGroupFrom<States.onHold>(transitionGroup =>
                        {
                            transitionGroup.Add(transition => 
                                transition.To<States.readyForAssignment>()
                                .IsTriggeredOn(graph => graph.ReleaseFromHold)
                                .When(!conditions.RequiresPrepayment));
                            transitionGroup.Add(transition => 
                                transition.To<States.pendingPayment>()
                                .IsTriggeredOn(graph => graph.ReleaseFromHold)
                                .When(conditions.RequiresPrepayment));
                        });
                    }))