private bool ExecuteSingleNode(NativeActivityContext context, FlowNode node, out FlowNode nextNode)
{
Fx.Assert(node != null, "caller should validate");
FlowStep step = node as FlowStep;
if (step != null)
{
if (_onStepCompleted == null)
{
_onStepCompleted = new CompletionCallback(this.OnStepCompleted);
}
return(step.Execute(context, _onStepCompleted, out nextNode));
}
nextNode = null;
FlowDecision decision = node as FlowDecision;
if (decision != null)
{
if (_onDecisionCompleted == null)
{
_onDecisionCompleted = new CompletionCallback <bool>(this.OnDecisionCompleted);
}
return(decision.Execute(context, _onDecisionCompleted));
}
IFlowSwitch switchNode = node as IFlowSwitch;
Fx.Assert(switchNode != null, "unrecognized FlowNode");
return(switchNode.Execute(context, this));
}
private void OnDecisionCompleted(NativeActivityContext context, ActivityInstance completedInstance, bool result)
{
FlowDecision decision = this.GetCurrentNode(context) as FlowDecision;
Fx.Assert(decision != null, "corrupt internal state");
FlowNode next = result ? decision.True : decision.False;
this.ExecuteNodeChain(context, next, completedInstance);
}