android - navigate to child activity in activity group in tabhost
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I have an application with a tabhost and one of the tabs is a ActivityGroup.
I want to navigate from Activity A1 in ActivityGroup GroupA to Activity B2 in ActivityGroup GroupB.
The main activity in GroupB is B1, but i want to go directly to B2.

I don't know how I can actually receive the ActivityGroup B object from my TabHost.

I can go to GroupB by using setCurrentTab(int index) on the TabHost.
But how can I get to Activity B2?