To build such kind of a report, we need to take the following steps:

1. Create a Free Format Report, which will combine Item Selector and Pie Chart 

2. Create a list of items to be included in the Item Selector

3. In Report Settings for Pie Chart controls set "External Item Selector" parameter to "Item Selector"

4. In Report Settings for Item Selector set "Item Selector" parameter to the required list of items

5. Optionally, you can set "Default Item Selector" and "Label Format" settings of Item Selector to the required values (see section Settings below).

As a result, we will get the report, where Pie Chart values are picked from the Item Selector list:

How to use other control as an Item Selector?

Now let's consider an example, when we do not want to use Item Selector as a separate control. Instead, we would like to combine a Table, a Pie and a Bridge controls in the Free Format Report. Then we will make the Pie "listen" to the Table rows - i.e. once we click on a particular row (which for example represents Account member), the values in the Pie and in the Bridge will be displayed according to this account.

To build such kind of a report, we need to take the following steps:

1.Create a Free Format Report, which will combine Table, Pie and Bridge controls (in our example we use account list for the table rows, Entities list for the pie chart )

2. In Report Settings for the Pie set "Item Selector" parameter to "Table"

As a result, we will get the report, where the pie is  changed according to the table rows:

Item Selector Settings

Basic Settings