InfoPath Dev

I have a drop-down list box, list box, and text box. I've cascaded the drop-down list box and the list box. Now, I want to connect the 2nd list box to the text box so that the text box is populated with the selection from the 2nd list box. After this, I want to be able to type text in the text box. So, for example, if I have the following scenario: Fruits and vegetables in the 1st drop down box. If I select fruits, the 2nd list box shows-Apple, Orange, Berries (I have been able to do this so far). If I select Apple, the text box should be populated with Apple and then let the user type text. Is there a way to do this? Thanks!

 Hi, You can put a rule on your drop down and populate your text box with the drop down value.

Thanks for the suggestion. I want to be able to type text after the text box is auto-populated with the entry from the drop box.

Ok, you can put a text box and hide it if it's empty, you add a drop down control of the same field and you show it only if it's empty.