Thursday, October 28, 2010

Nested Views in MVP


I have been reading the excellent article at:

And love the new built in objects that facilitate the MVP design
paradigm. My initial thought is great but how does this system cope
with Nested Views or Dock Panel style layouts where various elements
can be clicked and the widget that changes isn't necessarily always
the center one?

Looking at the example code given for HelloMVP it looks like when you
go to a new Place when the Activity is started by calling the start
method a widget is passed in that is the containerWidget or host for
that presenter:

public void start(AcceptsOneWidget containerWidget, EventBus
eventBus) {
GoodbyeView goodbyeView = clientFactory.getGoodbyeView();

Looking at the setup code from the onModuleLoad, a root SimplePanel is
added to the activity manager:


This widget is then passed to the start method each time a new place
is revealed. Thus causing a screen refresh? each time a new place is

How would you handle a scenario that has a Left hand menu (like gmail)
and a main container. Where clicking options in the LHS initiates a
new widget to be displayed in the center. Using the current logic it
looks like the whole screen is refreshed to show the newly selected
menu option and the center widget. Perhaps it does, and perhaps this
is ok, but it sounds hacky.

For example it would be nice if clicking a center widget not only
indicated what place to reveal but where that place/widget should be

I am sure this scenario is very common and it may have a lot to do
with my naivety with this new methodology. If anyone has any
pointers, opinions or examples on this it would be greatly


You received this message because you are subscribed to the Google Groups "Google Web Toolkit" group.
To post to this group, send email to
To unsubscribe from this group, send email to
For more options, visit this group at

No comments:

Post a Comment