Defining Discrete Values for a Property


When you add properties to an object class, you have to select whether you want a single value or discrete values. If you select discrete values, it means that the property will have predefined values - the user will not be able to enter a value but will have to select from a predefined list. Those values have to be created in a text file and stored in a specific directory. 
You also need to be familiar with project resource management to be able to create and store those discrete values.
Please refer to Understanding Project Resource Management.