Update notification's text in Android (depending on previous value)
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I'm implementing an application that receives messages and notifies you when you receive them. I want to implement a notification system similar to Whatsapp: if I receive only one message, the title of the message will be shown in the notification; if then I receive antoher one, the notification has to say I have two messages, and so on.

I wanted to get the previous contentText of the notification to be able to know how many messages has the user received until now and then add to it the number of messages received now, but I can't find how to get it. 

I found this in android-developers: "You can revise each property with the object member fields (except for the Context and the notification title and text)." Does this mean I can't get the contentText? If I can't get it, should I save the number in a static class or something like that?

Thanks!