How to customize ComboBoxItem to "list all" on space button?

[frank99]

I got a requirement on a ComboBoxItem that when a user hit a space button in the text input area of a ComboBoxItem, it displays all of the options in the pick list. Currently only the keyboard input Alt+arrow down key can do that.

How do I customize comboBoxItem to meet this requirement? I noticed that ComboBoxItem has setPickListCriteria() method, but I am not sure adding criteria is the right direction to go.

Thanks in advance!