Notifications opening activities and the back button? Restricting to one instance?
<p>There's a situation I have that's related to the Activity stack but I'm new enough to Android dev to not now how to respond to it.</p>

<p>I have an application that works like a stopwatch. When you start it, an ongoing notification goes in the notification tray and remains ongoing until you stop the stopwatch. I've noticed that if my stopwatch is running in the foreground, and I touch the notification, it creates a new instance of my stopwatch's activity and slides the old one off screen. This creates problems with the back button (you press back and the new instance goes away to reveal the old instance). It makes sense why this happens, but I don't want it to happen like this. What can I do to prevent multiple instances of my application from running?</p>
