The combobox items can be defined statically or dynamically.
The position and size of it can by adjusted with the standard plugin attributes.
The Flash CS4 source code (.fla) is available here (750kB).
The HTML5 default combobox base-image is available here.
Note - the old <action name="combobox:..."> syntax is officially not longer supported
and shouldn't be used in new projects, but it is still there for backward compatibility!
Should the native browser combobox element be used.
Settings: "false" (default), "true" or "auto"
With "auto" the native element will be used on Desktop and the not-native iPad-style one on iPhone and iPad.
Using the native one on iPhone/iPad would cause rendering problems and instability.
With native="false" it is possible to use the iPad-style combobox also on Desktop.
Select an item by its caption. Note - this can be problematic when the caption contains special or formating characters or was build dynamically!
Use the selectIdItem action instead.