You will have to use a Dashboard Action to achieve this. If i understand your requirement clearly, you have made 2 sheets - 1st is a list of Product Types and other is the sheet which renders a pie chart, and both are placed on a single Dashboard. You need the select the Product Types on the 1st sheet and the 2nd sheet will show relevant pie chart distributions accordingly.
You can go to Dashboard-> Actions -> Add Filter Action
Then under source, choose the 1st sheet; under target choose 2nd sheet. Make it to run on "Select" and Clearing the filter will "Show All Values"
If the fields in both data sources have same names, you can choose "All fields" under the fields section. Else you can select the "Selected Fields" radio button and match up the common fields for filtering purposes.
I hope this is clear; if not, request you to please post a sample data / workbook and I would be happy to help you. Thanks.