In-order for a button on an ABAP web dynpro to be functional you need to Add an action to it. First of all you need to insert a new element of type Button and entered its properties including text, image as usual. You then need to populate the action property with the action you want to be triggered. This can either be a new one or one that already exists within the web dynpro application. Once entered the action can be viewed from within the action tab. From this tab you can then access the method behind the action and add the appropriate code for performing whatever functionality you require when the user clicks on the button.