Android. How to programmatically change the microphone?

Question

Java

There is a pair: an Android smartphone and a bluetooth headset. When a call comes in, either the speaker and microphone of the machine, or the headphones and microphone of the headset work.
The application needs to implement functionality that will allow you to switch between microphones (either smartphone microphone or headset) and speakers (smartphone speaker - headphones).

Answer 1

Here is a ready-made example https://play.google.com/store/apps/details?id=com....
You can find the source codes at the link in the description

Answer 2

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