public static void lengthFilter(final Context context, final EditText editText, final int max_length, final String err_msg) {
InputFilter[] filters = new InputFilter[1];
filters[0] = new InputFilter.LengthFilter(max_length) {
@Override
public CharSequence filter(CharSequence source, int start, int end,
Spanned dest, int dstart, int dend) {
int destLen = StringUtils.getCharacterNum(dest.toString()); //获取字符个数(一个中文算2个字符)
int sourceLen =StringUtils.getCharacterNum(source.toString());
if (destLen + sourceLen > max_length) {
Toast.makeText(context, err_msg,Toast.LENGTH_SHORT).show();
return "";
}
return source;
}
};
editText.setFilters(filters);
}
附加方法：
/**
* @description 获取一段字符串的字符个数（包含中英文，一个中文算2个字符）
* @param content
* @return
*/
public static int getCharacterNum(final String content) {
if (null == content || "".equals(content)) {
return 0;
}else {
return (content.length() + getChineseNum(content));
}
}
/**
* @description 返回字符串里中文字或者全角字符的个数
* @param s
* @return
*/
public static int getChineseNum(String s) {
int num = 0;
char[] myChar = s.toCharArray();
for (int i = 0; i < myChar.length; i++) {
if ((char)(byte)myChar[i] != myChar[i]) {
num++;
}
}
return num;
}
摘自 青峰的博客
