Adding a Custom Data Source

To add a custom data source to the Web Part, do the following.

Navigation

In SharePoint, navigate to the Task List or Process Instance List Web Part.
On the Web Part window, click the Arrow button, and then click Edit Web Part. The Arrow button appears only when you move the pointer over the Web Part window.
The navigation for this task varies, depending upon your SharePoint version and the SharePoint settings in your local environment. For more information, see the documentation for SharePoint.
In the Web Part properties, click Data Sources.

On the Custom Data Sources Configuration Window window, select the item you want in the Available Sources list, and click Add.