POI实现省市级联（二级下拉框）

/* ** @Author * @Description 为excel工作表添加省市级联下拉框* @Date 11:51 2020/12/10* @Param [book 工作表, pullDownStartRow 下拉框起始行, pullDownEndRow 下拉框终止行, provinceCol 省份列, areaMap 以省份为key，城市数组为value] 行和列都是以0开始* @return void**/public static void cascade(Workbook book,int pullDownStartRow,int pullDownEndRow,int provinceCol,Map<String,String[]> areaMap,String sheetName) {// 获取需要用户填写的sheet（数据页，这里暂时为0，不开放，需要的时候再改）XSSFSheet sheetPro = (XSSFSheet) book.getSheetAt(0);// 获取省份（key）String[] provinceArr = areaMap.keySet().toArray(new String[0]);// 有子集的地址（可拓展为三级级联）String[] areaFatherNameArr = provinceArr;
//------------------------------------------------------------隐藏sheet开始（不需要修改）------------------------//创建一个专门用来存放地区信息的隐藏sheet页//因此也不能在现实页之前创建，否则无法隐藏。// sheetName 例子中为areaSheet hideSheet = book.createSheet(sheetName);//这一行作用是将此sheet隐藏，功能未完成时注释此行,可以查看隐藏sheet中信息是否正确book.setSheetHidden(book.getSheetIndex(hideSheet), true);int rowId = 0;// 设置第一行，存省的信息Row provinceRow = hideSheet.createRow(rowId++);provinceRow.createCell(0).setCellValue("一级列表");for(int i = 0; i < provinceArr.length; i ++){Cell provinceCell = provinceRow.createCell(i + 1);provinceCell.setCellValue(provinceArr[i]);}// 将具体的数据写入到每一行中，行开头为父级区域，后面是子区域。for(int i = 0;i < areaFatherNameArr.length;i++){String key = areaFatherNameArr[i];String[] son = areaMap.get(key);Row row = hideSheet.createRow(rowId++);row.createCell(0).setCellValue(key);for(int j = 0; j < son.length; j ++){Cell cell = row.createCell(j + 1);cell.setCellValue(son[j]);}// 添加名称管理器String range = getRange(1, rowId, son.length);Name name = book.createName();// 解决首字符只能是字母或者下划线问题if(!Character.isLetter(key.charAt(0))){key = "_"+key;}//key不可重复name.setNameName(key);String formula = sheetName+"!" + range;name.setRefersToFormula(formula);}//------------------------------------------------------------隐藏sheet结束（不需要修改）------------------------XSSFDataValidationHelper dvHelper = new XSSFDataValidationHelper((XSSFSheet)sheetPro);// 省规则DataValidationConstraint provConstraint = dvHelper.createFormulaListConstraint(sheetName+"!"+getRange(1,1,areaFatherNameArr.length));//DataValidationConstraint provConstraint = dvHelper.createExplicitListConstraint(areaFatherNameArr);// 四个参数分别是：起始行、终止行、起始列、终止列CellRangeAddressList provRangeAddressList = new CellRangeAddressList(pullDownStartRow, pullDownEndRow, provinceCol, provinceCol);DataValidation provinceDataValidation = dvHelper.createValidation(provConstraint, provRangeAddressList);//验证provinceDataValidation.createErrorBox("error", "请选择正确的值");provinceDataValidation.setShowErrorBox(true);provinceDataValidation.setSuppressDropDownArrow(true);sheetPro.addValidationData(provinceDataValidation);//对行设置有效性（endRow需要多加1才对的上省级级联共同的行数）for(int i = pullDownStartRow+1;i < pullDownEndRow+2;i++){setDataValidation(transCharByNum(provinceCol) ,sheetPro,i,provinceCol+2);}}/* ** @Author * @Description 输入0返回A 输入1返回B* @Date 11:17 2020/12/10* @Param [num]* @return java.lang.String**/public static String transCharByNum(Integer num){return new Character((char)(num.toString().getBytes()[0]+17)).toString();}/*** 设置有效性* @param offset 主影响单元格所在列，即此单元格由哪个单元格影响联动* @param sheet* @param rowNum 行数* @param colNum 列数*/public static void setDataValidation(String offset,XSSFSheet sheet, int rowNum,int colNum) {XSSFDataValidationHelper dvHelper = new XSSFDataValidationHelper(sheet);DataValidation data_validation_list;data_validation_list = getDataValidationByFormula("INDIRECT($" + offset +"$"+ (rowNum) + ")", rowNum, colNum,dvHelper);sheet.addValidationData(data_validation_list);}/* ** @Author * @Description 定义公式校验* @Date 12:43 2020/12/10* @Param [formulaString, naturalRowIndex, naturalColumnIndex, dvHelper]* @return org.apache.poi.ss.usermodel.DataValidation**/private static DataValidation getDataValidationByFormula(String formulaString, int naturalRowIndex, int naturalColumnIndex,XSSFDataValidationHelper dvHelper) {// 加载下拉列表内容// 举例：若formulaString = "INDIRECT($A$2)" 表示规则数据会从名称管理器中获取key与单元格 A2 值相同的数据，//如果A2是江苏省，那么此处就是江苏省下的市信息。XSSFDataValidationConstraint dvConstraint = (XSSFDataValidationConstraint) dvHelper.createFormulaListConstraint(formulaString);// 设置数据有效性加载在哪个单元格上。// 四个参数分别是：起始行、终止行、起始列、终止列int firstRow = naturalRowIndex -1;int lastRow = naturalRowIndex - 1;int firstCol = naturalColumnIndex - 1;int lastCol = naturalColumnIndex - 1;CellRangeAddressList regions = new CellRangeAddressList(firstRow,lastRow, firstCol, lastCol);// 数据有效性对象// 绑定XSSFDataValidation data_validation_list = (XSSFDataValidation) dvHelper.createValidation(dvConstraint, regions);data_validation_list.setEmptyCellAllowed(false);if (data_validation_list instanceof XSSFDataValidation) {data_validation_list.setSuppressDropDownArrow(true);data_validation_list.setShowErrorBox(true);} else {data_validation_list.setSuppressDropDownArrow(false);}// 设置输入信息提示信息data_validation_list.createPromptBox("下拉选择提示", "请使用下拉方式选择合适的值！");// 设置输入错误提示信息//data_validation_list.createErrorBox("选择错误提示", "你输入的值未在备选列表中，请下拉选择合适的值！");return data_validation_list;}/***  计算formula（因为下拉框poi导出用createExplicitListConstraint(arr)最多只能有52个，所以需要更换方法，*  更换为createFormulaListConstraint(listFormula).传入参数是一个引用，引用某张表的连续数据，所以应该是传入$B$1:$K$1类似的值）*  此方法为计算传入参数* @param offset 偏移量，如果给0，表示从A列开始，1，就是从B列* @param rowId 第几行* @param colCount 一共多少列* @return 如果给入参 1,1,10. 表示从B1-K1。最终返回 $B$1:$K$1**/public static String getRange(int offset, int rowId, int colCount) {char start = (char)('A' + offset);// 25和26以及51是因为Excel的列名是从A-Z,然后AA-AZ，然后BA-BZ以此类推，每过26个字母需要做不同的处理，所以这些常数这里不用改if (colCount <= 25) {char end = (char)(start + colCount - 1);return "$" + start + "$" + rowId + ":$" + end + "$" + rowId;} else {char endPrefix = 'A';char endSuffix = 'A';if ((colCount - 25) / 26 == 0 || colCount == 51) {// 26-51之间，包括边界（仅两次字母表计算）if ((colCount - 25) % 26 == 0) {// 边界值endSuffix = (char)('A' + 25);} else {endSuffix = (char)('A' + (colCount - 25) % 26 - 1);}} else {// 51以上if ((colCount - 25) % 26 == 0) {endSuffix = (char)('A' + 25);endPrefix = (char)(endPrefix + (colCount - 25) / 26 - 1);} else {endSuffix = (char)('A' + (colCount - 25) % 26 - 1);endPrefix = (char)(endPrefix + (colCount - 25) / 26);}}return "$" + start + "$" + rowId + ":$" + endPrefix + endSuffix + "$" + rowId;}}public static void main(String[] args) {Map<String,String []> map = new HashMap<>();map.put("一级字段1",new String[]{"二级字段1.1","二级字段1.2","二级字段1.3"});map.put("一级字段2",new String[]{"二级字段2.1","二级字段2.2","二级字段2.3","二级字段2.4"});XSSFWorkbook sheets = new XSSFWorkbook();XSSFSheet aaa = sheets.createSheet("aaa");aaa.createRow(0).createCell(0).setCellValue(0);cascade(sheets,1,100,3,map,"area");FileOutputStream os = null;try {os = new FileOutputStream("D:/testabc.xlsx");sheets.write(os);} catch (Exception e) {e.printStackTrace();} finally {IOUtils.closeQuietly(os);}}

测试结果