Binding variables of application class in bsp application.

Question

Hi,
I know it is possible to bind the variables of model class like "//MODEL/VARIABLE" but is it possible to bind the variables of applicaiton class?
Thanks and regards,
Santosh.

Answer 1

You have to remember that BSP evolved over several releases.  In 6.10 BSP released with no support for MVC - just the Application class. The application class was simply the way to share values between views and store them between requests in stateful applications.  It doesn't support any data binding.  In 6.20 BSP began to support MVC with the introduction of controller classes and model classes.  You data bind UI elements directly to model attributes only.  There is no concept of context.
WD is completely different in that you only data bind UI element to the a context. The MVC structure is much cleaner because the view layout never has visibility to the model (regardless of what you consider the model). 
Over time the assistance class has become the defacto standard for models in WDA, because unlike WDJ there is no direct model object.  It originally was intended mostly as a way of having text elements for WDA components.  However it is still perfectly acceptible to use service calls (proxy objects, function modules, class methods) as your model. I personally prefer to always wrap calls to my service object up in an assistance class for clear design.