I am building a calculator using the button widgets, but i have problem in executing the same service on the click event of the button.
I have mapped the text area text to the existingexp parameter of the service, and the output of the service back to textarea.
Also i have mapped all the events of the button to call the service.
But the concatenatingexp parameter of the service has to change based on what button i have clicked and respective text has to get appended.
I see that i ll not be allowed to assign concatenatingexp parameter with multiple inputs from various buttons.
In this case how would i go with it.