Hi Ralph
First thanks for answering my question.
I'm using RTC 4.0.6.
What I want to achieve is store in hidden attributes the last date(timestamp) of a certain action (I say last because an action can be done several times , like a reopen).
I have achieved that i store in a hidden attribute the first date when the workitem gets to an state.But its only the first date. Because when I tried to make a script that updates whenever it gets to the same state , it also saved the date when I modified something on that state.

How can I stored the previous state in a hidden ?Because  I think that the work item actually runs the script twice (when you click  the action and when you click save I think).

Thanks!

You can only save the state (from the attribute state) you have access to. If you do that, I think you should be able to detect that the current state is not equal to the state value in the attribute. Only in this case you know a change has been done and can act upon it. If the current state equals the attribute value you would not know what is going on and also not provide the attribute value, or rather pass the old value of the attribute.

Yes, calculated value providers run multiple times, to act upon changes to the values they depend on.

Hy Ralph, Hy Cesar,

I might have a little Idea.
I've made a "Set Done"-Button in a widget I created.
There we could direct see, which state a WorkItem is.
And I would say, you should simply store it as a String.
i.E. date;state --> 01:01:2014:00:00:00;open
just use string.slice(";");
Et voila you have your two values.

//This is how I get to the state of a workitem
//this.currentId is the ID of the specifiv workitem
this.workingCopyProxy = WorkItemProxyFactory.getWorkItemProxy({id: this.currentId, createIfNeeded: true, doNotCache: true, doNotGetFromCache:true});
this.workingCopyProxy.initialize({});

var proxyState = this.workingCopyProxy.getValue({path: 'attributes.internalState.label'});
proxyState == 'Done'