I have a fixed content in my text view inside a scroll view. When the user scrolls to a certain position, I would like to start an activity or trigger a Toast.<
Starting from API 23 Android M, you can use OnScrollChangeListener.
scrollView.setOnScrollChangeListener(new View.OnScrollChangeListener() {
@Override
public void onScrollChange(View v, int scrollX, int scrollY, int oldScrollX, int oldScrollY) {
//work with parameters
}
});