title: Clear EditText text after adding onTextChanged implemenation
body: <p>I'm adding a listener to an EditText field to appropriately format the number to currency in real time.</p>
  
  <pre><code>        loanText.addTextChangedListener(new TextWatcher() {
          private String current = "";
          public void onTextChanged(CharSequence s, int start, int before, int count) {
              if(!s.toString().equals(current)){
                 String cleanString = s.toString().replaceAll("[$,.]", "");
  
                 double parsed = Double.parseDouble(cleanString);
                 String formated = NumberFormat.getCurrencyInstance().format((parsed/100));
  
                 current = formated;
                 loanText.setText(formated);
                 loanText.setSelection(formated.length());
              }
          }
          public void afterTextChanged(Editable s) {
              // TODO Auto-generated method stub
  
          }
          public void beforeTextChanged(CharSequence s, int start, int count,
                  int after) {
              // TODO Auto-generated method stub
  
          }
      });
  </code></pre>
  
  <p>However, when I try to clear the EditView field, my App will crash. In addition, the backspace key no longer functions.</p>