Cascading Select Boxes … How To?

Hello All

This is my first time using this forum so I hope it will be successful.

I am building a site for a client using:-

WP 4.3.1
Wordpress Front End 2.3.10
Woocommerce 2.4.7

This is more of a technical “How do I do this” than an issue …

I have a range of products covered by 6 top level categories. He wants people to add products to my site. However Once the main category is selected I then need the first DROPDOWN BOX on the product entry form to only show the first level PRODUCT ATTRIBUTE based on the CATEGORY.

So for example if I select CATEGORY 1 on the input form then I want the product attributes to show as follows.

PRODUCT_CATEGORY_1

——-PRODUCT_ATTRIBUTE_1

————–PRODUCT_ATTRIBUTE_3
————–PRODUCT_ATTRIBUTE_4
————–PRODUCT_ATTRIBUTE_5

——-PRODUCT_ATTRIBUTE_6

————–PRODUCT_ATTRIBUTE_7
————–PRODUCT_ATTRIBUTE_8
————–PRODUCT_ATTRIBUTE_9

If I select CATEGORY 2 then the dropdown should only show values as follows

PRODUCT_CATEGORY_2

——-PRODUCT_ATTRIBUTE_10

————–PRODUCT_ATTRIBUTE_11
————–PRODUCT_ATTRIBUTE_12

——-PRODUCT_ATTRIBUTE_13

————–PRODUCT_ATTRIBUTE_14
————–PRODUCT_ATTRIBUTE_15
————–PRODUCT_ATTRIBUTE_16
————–PRODUCT_ATTRIBUTE_17

Now – I understand that I MAY have to use CATEGORIES and not ATTRIBUTES – however I will need to write the selections from the dropdown boxes into the attributes so that the shop is still searchable with Woocommerce Layered Nav.

Any help, Guidance or instruction that can be given will be greatly appreciated.

I am happy to give more information if I haven’explained it well enough.

Many Thanks

[ No bumping please. ]