When creating multi-instance tasks, there always seems to be one task without an assigned person responsible.

  <process id="dynamicDepartmentProcess" isClosed="false" name="动态部门审批流程" processType="None">
    <startEvent id="startevent1"/>
    <userTask activiti:assignee="${currentAssignee}" activiti:exclusive="true" id="currentTask" name="当前审批">
      <extensionElements>
        <activiti:taskListener class="com.itheima.listener.DynamicDepartmentListener" event="complete"/>
      </extensionElements>
    </userTask>
    <userTask activiti:assignee="#{nextApproverList[loopCounter-1]}" activiti:exclusive="true" activiti:formKey="departmentForm" id="departmentTask" name="部门审批">
      <multiInstanceLoopCharacteristics activiti:collection="nextApproverList" isSequential="false">
        <loopCardinality><![CDATA[#{nextApproverCount}]]></loopCardinality>
      </multiInstanceLoopCharacteristics>
    </userTask>
    <endEvent id="endevent1"/>
    <sequenceFlow id="flow1" sourceRef="startevent1" targetRef="currentTask"/>
    <sequenceFlow id="flow2" sourceRef="currentTask" targetRef="departmentTask"/>
    <sequenceFlow id="flow3" sourceRef="departmentTask" targetRef="endevent1"/>
  </process>

@Slf4j
public class DynamicDepartmentListener implements TaskListener {

    @Override
    public void notify(DelegateTask delegateTask) {
        // 获取当前任务的处理人
        String currentAssignee = delegateTask.getAssignee();

        // 根据当前处理人决定下一级部门列表
        List<String> nextApproverList = getDepartmentsByCurrentUser(currentAssignee);

        // 获取流程引擎
        ProcessEngine processEngine = ProcessEngines.getDefaultProcessEngine();
        RuntimeService runtimeService = processEngine.getRuntimeService();

        // 设置流程变量
//        runtimeService.setVariable(delegateTask.getProcessInstanceId(), "nextApproverList", nextApproverList);
//        runtimeService.setVariable(delegateTask.getProcessInstanceId(), "nextApproverCount", nextApproverList.size());

        delegateTask.getExecution().setVariable("nextApproverList", nextApproverList);
        delegateTask.getExecution().setVariable("nextApproverCount", nextApproverList.size()+1);
        //这里有bug，最后一个的负责人总是null
        //我指定是三个人，需要给定大小为4，才能完整展示，但是第四个还是null
        //设置大小为3会少一个负责人
        //不管了
        log.info("动态设置下一级部门: {}",nextApproverList);
    }

    private List<String> getDepartmentsByCurrentUser(String currentAssignee) {
        // 这里实现根据当前处理人决定下一级部门的逻辑
        // 例如：根据当前用户所属部门，查询需要审批的部门列表
        List<String> departments = new ArrayList<>();

        // 示例：根据当前用户返回部门列表
        if ("jack".equals(currentAssignee)) {
            departments.add("rose");
            departments.add("tom");
            departments.add("jerry");
        } else if ("director".equals(currentAssignee)) {
            departments.add("rose");
            departments.add("tom");
        }

        return departments;
    }
}