I am a student programmer and the topic my degree work is to finalize one of the input methods for touchscreen devices by visually impaired people (including the blind). I want to make my application work correct with TalkBack. But I totally don't know, how to do it. I've found the package for accessibility, but it's not clear for me, how to it integrates with TB.
As an application developer, you don't need to specifically integrate your app with TalkBack. Instead, you should focus on providing correct data to the accessibility framework. This will ensure that your application works not only with TalkBack, but also with Braille and switch-based accessibility services.
See the Android Developer guide on Making Applications Accessible for an overview of what steps you need to take to ensure your application works correctly with accessibility services.
You may also want to watch the Google I/O 2012 talk Making Android Apps Accessible, which covers basic application accessibility.