Adobe Cs5 flash, components

Hi.

Please have a look at this answer:

actionscript 3 - ComboBox Text Formatting through AS3 - Stack Overflow​

Alright well the ComboBox is a container which contains the TextField and the DropDown List. So you can't directly apply the setStyle on ComboBox itself rather you need to apply it to the specific element inside the ComboBox.

import flash.text.TextFormat;
//Text Formats that needs to be applied on your comboBox
var txtformat:TextFormat = new TextFormat();
txtformat.size = 30;
//Lets just increase the size of fonts
//Increase the main TextField's font size of your ComboBox
yourComboBox.textField.setStyle("textFormat", txtformat);
//Increase the font size of dropDownList items
yourComboBox.dropdown.setRendererStyle("textFormat", txtformat);

I hope this helps.

Regards,

JC