Hi I am a web developer, writing complex widgets and managing their flow, sometimes I feel that I need to know some patterns and practices in GUI programming in general. I am aware of observer pattern, command pattern etc. But I want to know something more ... wondering how "facebook" manages their widgets controls. Suppose i will go through a number of widgets depending on user input on each stage, i want to have a plan to go though all the widgets, and call the feedback functions as well. Is there anything to help me.