mobile_et.addTextChangedListener(textWatcher);     /**      * 实时监听用户输入的手机号，输入至最后一位后，计算折扣后的金额      */     TextWatcher textWatcher = new TextWatcher() {         @Override         public void onTextChanged(CharSequence s, int start, int before, int count) {             // TODO Auto-generated method stub         }         @Override         public void beforeTextChanged(CharSequence s, int start, int count,                 int after) {             // TODO Auto-generated method stub         }         @Override         public void afterTextChanged(Editable s) {             if(s.length() == 11){                 String amountYuan = amount_et.getText().toString();//用户选择的金额+元                 String mobileNum = mobile_et.getText().toString().trim();                 int tMobile = Utils.getMobileOp(mobileNum);                 String disAmount= getDisAmount(tMobile, amountYuan);                 amount_discount_tv.setText(disAmount);             }         }     };