How to set distinct I2C slave addresses during run-time?

I need to set distinct I2C slave addresses for a couple of RX23T microcontrollers using GPIO pins. But the code generator tool requires that I set a predefined value as the address.

Is it possible to not assign an address in the software and assign it during run-time after reading the state of the GPIO pins?

 

I've attached the screenshot of the code generator tool for a better understanding.

 

I2C_Slave_Mode