How can i add change event in properties panel dropdown and populate other dropdown

How can i add onchange event in properties panel dropdown and poulate other dropdown .

I have a IO and Condition dropdown in properties panel,
I have to populate condition dropdown based on IO selection. how can i get this done in Properties panel?

The properties panel rerenders whenever an element’s property has changed. Is the first input changing an element’s property? Can you show a sketch of what you’re trying to achieve?