限制EditText 输入的字节数

1、代码

         name_tv = (EditText) findViewById( R.id.name_tv );

         name_tv.addTextChangedListener(new TextWatcher() {
             @Override
             public void beforeTextChanged(CharSequence s, int start, int count, int after) {
             }

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

             @Override
             public void afterTextChanged(Editable s) {
                 String string = s.toString().trim();

                 //限定输入框最多输入18个字节
                 int inputLength = string.length();
                 int byteLength = string.getBytes().length;
                 if (byteLength >= 18) {
                     name_tv.setFilters(new InputFilter[]{new InputFilter.LengthFilter(inputLength)});
                 } else {
                     name_tv.setFilters(new InputFilter[]{new InputFilter.LengthFilter(18)});
                 }
                 name_tv.setSelection(name_tv.getText().toString().length());
             }
         });