Types of automation links

Pega Robot Studio™ projects use threads to paint the screen with the project's windows, application bars, Windows forms, the associated controls, execute automations, and integrate with the project applications. At project runtime, when users interact with a Windows form or its child controls, Windows sends messages describing the users activity to the user interface thread.

The user interface processes hundreds of messages every second. In response to these messages, the user interface thread raises Windows form events such as Click, KeyPressed, or TextChanged.

All Windows form events raise synchronously and execute on the user interface thread. Since the user interface thread is responsible for painting the screen, any long-running activity that occurs on the user interface thread can block both painting and message processing.

This gives users the impression that the user interface is not responding. To avoid this, any automation triggered by a Windows form event should execute an asynchronous link to release the user interface thread before it interacts with any adapter controls or non-Windows form components, such as web services or data access.

Use the event link Design properties to set asynchronous/synchronous execution. You may also right-click on the automation link and select Asynchronous.

The asynchronous link resembles a yellow dash line in the automation.