Hello,
is there is any way where I can get an indication when any events are completed.
For example if I crash my app manually and start the same with startActivity(main), then I want an indication, when the startActivity(main) get finished
Not sure what you are doing but it sounds like this is not the correct solution. You can also can't start activities when the app is in the background in Android 10+.
I have a feeling that you should switch to B4XPages.
I think that you have the wrong picture of an event. An event is over in an instant - there is time before the event and time after the event. The event takes no time at all. So "downloadComplete" simply means that the download is complete.
In situations when the duration of an operation is relevant then the operation would be marked by two events, such as "download_starting" before the download started and "download_finished". But normally an event indicates that the operation is complete.