How to start an activity from a singleInstance activity?

I have a widget which can pop up small dialogs when clicked. These dialogs are displayed by an activity called RemoteActivity in singleInstance launchMode. In one of these dialogs, there is a button to launch the main app MainActivity, which has the standard launchMode.

However, when this button is clicked, and startActivity() called, MainActivity isn't launched, although I can see the corresponding "Starting activity: Intent { ... }" in logcat.

If I set the launchMode of RemoteActivity to standard then MainActivity gets launched, but this isn't what I want, RemoteActivity is merely an extension of the widget, I don't want it to stack with any other activity.

I also tried with FLAG_ACTIVITY_NEW_TASK but it didn't help, and it shouldn't be necessary anyway according to the docs:

A "singleInstance" activity, on the other hand, permits no other activities to be part of its task. It's the only activity in the task. If it starts another activity, that activity is assigned to a different task — as if FLAG_ACTIVITY_NEW_TASK was in the intent.

How can I launch my main activity?

UPDATE / ERRATA:

The MainActi开发者_StackOverflowvity is actually launched but only if it isn't already part of a task. If I launch MainActivity normally through the launcher, and press Back to exit, then RemoteActivity does launch MainActivity.

But if, instead of pressing Back, I press Home to leave MainActivity, then RemoteActivity can't launch MainActivity, although the intent appears in logcat.

I'm testing this on Froyo.

Any idea of what's happening?

Maybe the noHistory flag will work for what you are looking for?

I found the problem: this behavior only occurs when calling finish() before startActivity() in RemoteActivity. If I call startActivity() before finish() then it works fine whether MainActivity is already part of an existing task or not.

Go figure...