I am developing app in Xamarin Android and have a very strange problem: Breakpoints and Exceptions have stopped working properly. When I set a breakpoint it never gets hit. I have set breakpoints all over my project but none of them were hit. This happens in Visual Studio and in Xamarin Studio as well.
I also have second and more annoying problem, every time there is an exception, it throws totally unhelpful "java.lang.reflect.InvocationTargetException" exception in Xamarin Studio and "An Exception occurred" in Visual Studio, with no more details about the exception. This happens only in one particular project, other projects work fine. I have looked for the solution in various forums and blogs but none of them worked. I am pretty new to Xamarin Android development and hope you can help me.
Possibly related too:
Bug 30318 - [Android] Windows only: Breakpoints in PCL projects do not work after cleaning solution, redeploying, and restarting debugging. Partial workaround: delete all the bin folders in the solution after cleaning.
Deleting the bin and obj folders has been fixing the issue for me, I'm on v. 3.11.586.
来源：https://stackoverflow.com/questions/30987318/breakpoints-and-exceptions-stopped-working-properly-xamarin-android