Android - Black Screen after clicking BACK in an Activity with an AltertDialog after Search Activity

I have an Activity which displays an alert dialog priot to the content. Also a search activity is called before this activity.

Now when i press back on this activity i am lead to a black screen (which i assume is eighter because of the dialog [unl开发者_运维知识库ikely] or from the search activity). Only when i press BACK twice i get to the activity i was before.

How can i get rid of this?

Thank you.

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This phenomenon was caused by the search activity. to avoid this i simply added android:noHistory="true" for the Search Activity in the Manifest.