presently created the position and size of the constituent part are changed on the work area 17 at step s23 the constituent part created at step s19 as well as the constituent part correlated with the view at step s22 is held by the form manager 5 at step s24 constituent parts are edited as required from the part editor area 18 on the display screen 11 by setting attribute values for the individual constituent parts and or writing event functions constituent parts retained by the form manager 5 are saved in the part storage 7 by selecting a save button 19 in the part editor area 18 obviously when constituent parts read out at step s16 are used just as they are such editing recording of the constituent parts is not required at step s25 decision is made by the gui creator 1 whether or not all the constituent parts of the object form have been created if not all the constituent parts have been created the program returns to step s13 and proceeds to creation of a next constituent part if all the constituent parts have been created the form creating operation ends and the program advances to step s4 in the flow chart of gui creating operation fig7 is a detailed flow chart of the control definition interpreting operation which is executed at aforesaid step s19 in the.