may i know what is different viewstack and states in flex ?

Question

In my flex project i used one option like Link button . If i like it will be open new page contain more information and components . Which container is suitable one ? Where is used viewstack and stages ? if you know please explain it . or refer me

Answer 1

With states you can have objects in each state with the same id - this cannot be done with a viewstack. Usually states are used when a group of objects are shared amongst the different "states" or "views". So for example you can have a textinput in each one of your states and give each one the same id of "username". When you reference the "username" id it will use the object in the currently enabled state. If you try to do this with a viewstack it will throw an error saying you've defined an id of "username" multiple times.

So as a wrap up... use states when you're adding or removing components from a set of components shared throughout each state. Use a viewstack when each view is different and do not share components.

Answer 2

Use states when your views are very similar and only differ based on a few controls or components. If you have too many AddChild / RemoveChild elements it becomes more difficult for a developer to follow your code.

A ViewStack also supports deferred instantiation through the "creationPolicy" attribute. This means that only the first Container in a ViewStack will be initialized when the ViewStack loads. This can really speed up load time of your application if you (A) have a lot of children in the ViewStack or (2) the children are large / complex components.