EditText.setFilters always over write the origin filters，buggly...

setMaxLengthFilter.java

public void setMaxLengthFilter(EditText editText, int maxLength) {
        InputFilter curFilters[];
        InputFilter.LengthFilter lengthFilter;
        int i;
        lengthFilter = new InputFilter.LengthFilter(maxLength);
        curFilters = editText.getFilters();
        if (curFilters != null) {
            for (i = 0; i < curFilters.length; i++) {
                if (curFilters[i] instanceof InputFilter.LengthFilter) {
                    curFilters[i] = lengthFilter;
                    return;
                }
            }

            InputFilter newFilters[] = new InputFilter[curFilters.length + 1];
            System.arraycopy(curFilters, 0, newFilters, 0, curFilters.length);
            newFilters[curFilters.length] = lengthFilter;
            editText.setFilters(newFilters);
        } else {
            editText.setFilters(new InputFilter[]{lengthFilter});
        }
    }