28、editText只输入英文字母和'-'，用于授权码输入

InputFilter filter = new InputFilter() {

            @Override
            public CharSequence filter(CharSequence source, int start, int end,
                    Spanned dest, int dstart, int dend) {
                // TODO Auto-generated method stub
                for (int i = start; i < end; i++) 
                {
                    //在这里判断输入的只能是英文字母和符号'-'
                    if (!Character.isLetter(source.charAt(i))
                            && source.charAt(i) != '-') 
                    {
                        return "";
                    }
                }
                return null;
            }
        };

        etActivteCode.setFilters(new InputFilter[] { filter });
        etActivteCode.addTextChangedListener(new TextWatcher() {

            @Override
            public void onTextChanged(CharSequence s, int start, int before,
                    int count) {
                // TODO Auto-generated method stub

                etActivteCode.removeTextChangedListener(this);// 解除文字改变事件

                if ((s.length() == 4 || s.length() == 9 || s.length() == 14)) {
                    etActivteCode.setText(s.toString().toUpperCase() + "-");// 转换
                } else {
                    etActivteCode.setText(s.toString().toUpperCase());// 转换
                }

                etActivteCode.setSelection(s.toString().length());// 重新设置光标位置
                etActivteCode.addTextChangedListener(this);// 重新绑
                String licensePlateNumber = etActivteCode.getText().toString()
                        .trim();
            }

            @Override
            public void beforeTextChanged(CharSequence s, int start, int count,
                    int after) {
                // TODO Auto-generated method stub
            }

            @Override
            public void afterTextChanged(Editable s) {
                // TODO Auto-generated method stub

                if (s.length() == 19) {
                    buttonActivate.setVisibility(View.VISIBLE);
                    InputMethodUtils.HideKeyboard(etActivteCode);
                }

            }
        });
        etActivteCode.setOnKeyListener(new OnKeyListener() {
            @Override
            public boolean onKey(View v, int keyCode, KeyEvent event) {
                // TODO Auto-generated method stub
                if (keyCode == KeyEvent.KEYCODE_DEL) {
                    CommonUtils.LogWuwei(tag, "delete");
                    etActivteCode.setText("");
                    buttonActivate.setVisibility(View.INVISIBLE);
                }
                return false;
            }
        });
    }

效果如下: