This method is called to notify you that, somewhere within s, the text has been changed. It is legitimate to make further changes to s from this callback, but be careful not to get yourself into an infinite loop, because any changes you make will cause this method to be called again recursively. (You are not told where the change took place because other afterTextChanged() methods may already have made other changes and invalidated the offsets. But if you need to know here, you can use Android.Text.ISpannable.SetSpan(Java.Lang.Object, System.Int32, System.Int32, System.Int32) in Android.Text.ITextWatcher.OnTextChanged(Java.Lang.ICharSequence, System.Int32, System.Int32, System.Int32) to mark your place and then look up from here where the span ended up.

[Android Documentation]