I just got burned by a widget. I could see the cause of the problem, but I could not determine why or its solution. My widget was issuing a search (SearchManager) and the activity launched a search dialog, but when it called-back to my widget, it created another reference to the widget (i.e., the thread-id was the same, but the widget-id changed from 65 to 0).
This led me to believe that a new instance was getting created and I searched the documentation for settings that would apply to the problem. Eventually, I stumbled upon the android:launchMode="singleTop" and as soon as I set it in the AndroidManifest, viola! My widget worked.
This took me the better part of two days to debug.
Are there any other situations or is there a more technically-correct answer to my problem?