android EditText 限定中文个数与英文个数的解决方式

EditText 限定中文8个英文16个的解决方法。在EditText上控件提供的属性中有限定最大最小长度的方法。可是，对于输入时，限定中文8个英文16个时，怎么办？相当于一个中文的长度是两个英文的长度。原理就不说了。自己看一下android的源代码。以上直接上代码。

private final int maxLen = 16;
private InputFilter filter = new InputFilter() {@Override
    public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {int dindex = 0;
        int count = 0;
        while (count <= maxLen && dindex < dest.length()) {char c = dest.charAt(dindex++);
            if (c < 128) {count = count + 1;
            } else {count = count + 2;
            }}if (count > maxLen) {return dest.subSequence(0, dindex - 1);
        }int sindex = 0;
        while (count <= maxLen && sindex < source.length()) {char c = source.charAt(sindex++);
            if (c < 128) {count = count + 1;
            } else {count = count + 2;
            }}if (count > maxLen) {sindex--;
        }return source.subSequence(0, sindex);
    }};

使用例如以下：

editText.setFilters(new InputFilter[]{filter});