InputFilter inputFilter= new InputFilter() {
    Pattern emoji = Pattern.compile("[\ud83c\udc00-\ud83c\udfff]|[\ud83d\udc00-\ud83d\udfff]|[\u2600-\u27ff]",
        Pattern.UNICODE_CASE | Pattern.CASE_INSENSITIVE);

    @Override
    public CharSequence filter(CharSequence source, int start, int end, Spanned dest, int dstart, int dend) {
      Matcher emojiMatcher = emoji.matcher(source);
      if (emojiMatcher.find()) {
        //          Toast.makeText(MainActivity.this,"不支持输入表情", 0).show();
        MyToast.showText("不支持输入表情");
        return "";
      }
      return null;
    }
  };

//给editText设置filter
edit_name.setFilters(new InputFilter[]{inputFilter,new InputFilter.LengthFilter(12)});

InputFilter inputFilter=new InputFilter() {

    Pattern pattern = Pattern.compile("[^a-zA-Z0-9\\u4E00-\\u9FA5_]");
    @Override
    public CharSequence filter(CharSequence charSequence, int i, int i1, Spanned spanned, int i2, int i3) {
     Matcher matcher= pattern.matcher(charSequence);
      if(!matcher.find()){
        return null;
      }else{
        MyToast.showText("只能输入汉字,英文，数字");
        return "";
      }

    }
  };