Detect backspace in TextWatcher

Question

I am using TextWatcher and I am unable to detect Backspace key in TextWatcher.afterTextChange event. I also want to clear textView on some condition in textWatcher event.

public void afterTextChanged(Editable s) {
    // TODO Auto-generated method stub
    // I want to detect backspace key here
}

Answer 1

To detect a backspace in TextWatcher, you can check the variable count that is passed into the onTextChange function (count will be 0 if a backspace was entered), like this:

@Override
public void onTextChanged(CharSequence cs, int start, int before, int count) {

  if (react) {
    if (count == 0) {
      //a backspace was entered
    }

    //clear edittext
    if(/*condition*/) {
      react = false;
      setText("");
      react = true;
    }
  }
}

The react boolean is needed for the setText() function otherwise it becomes recursive. Hope this helps!