Considering the complexity of ARINC661 cockpit display and control system in realizing target symbols,and the heavy workload of DF developer,we studied the user-defined widgets and parameter interfaces on the basis of ARINC661 specification,and designed a new type of display item.It can present complex composite target symbols in accordance with the setting information in the definition files and the configuration information in the UA instruction.The simulation results show that the design is reasonable and reliable,which can greatly reduce the size of predefined symbol library and the workload of DF developer without increasing the CDS memory usage and communication data.It is also convenient for later maintenance.