This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
I just have a quick question regard when a value/backing bean should be used over a binding. This is something that there seems to be a lack of clarity over in any of the documentation I've read and seems to cause problems in certain action methods and value change listeners. Typically I use JavaBeans to model my data (lightweight classes that basically have getter/setter methods to hold data) and these are linked via handler classes (which I have set up as managed beans in the faces-config.xml file) to value fields in my JSPs. This all works well on output screens and input forms except in two particular scenarios: a "clear" action to clear the contents of a form and on linked drop down fields (i.e. where the contents of one drop down field determines the contents of another) whose states are maintained by value change listeners. I've found that by manipulating the state of my JavaBeans, these changes are not always reflected in my JSPs because their values seem to be linked to their component bindings.
Can any offer any advice in this area? I should mention that I'm using the Apache Trinidad JSF framework, which seems to have it's own small quirks.
binding and values are two really different things. I will give you a short description on both.
Value on one hand is used to assign value to the component while binding is used to bind a component itself to some reference in the backing bean. Then you can change the properties of the binded component in the backing bean itself.