You only have to disclose if you are CCing and only if you are stopped or detained.
A LEO coming to your door for the purpose of asking questions depends.
Is the LEO detaining you? If so and you are CC you must disclose.
If the LEO just is asking have you seen any suspicious activity around the neighborhood or something of that nature then I would not feel I was detained and therefor would not see any need to disclose I am armed.
The same goes for if you call the police for something that has nothing to do with your gun. IMOP they have no need to know I am armed if I am CC. If I am OC and they don't notice oh well.. as they are on my property if they have a problem with it oh well.