GWT - MVP

My application has several modules, and in each module, it may have different layout. Hence I have multiple level of Activity and in each module, I have an ActivityManager and ActivityMapper to create an appropriate Activity according to the Place or return null if not interested.  All the ActivityManagers are attached to a global Event bus.

you can separate your project into two modules: A module containing model and persistence code that is created by Spring Roo A GWT web application that you create by hand. Make the first (Roo) module a dependency of the second (GWT) module. Basically you're using Roo to create a JAR library that's used by your web application. As long as you don't run the controller command the Roo won't add any web application code to your module.

've started prototyping with Activities and can now give some more feedback on how it compares to my previous own implementation of a PlaceManager and how I used it with MVP.

use the history and pass the information as parameters in the history token.

has a number of advantages provided the parameter is serializable (and small enough). For example, it could let the user bookmark the detail page of "Lady_Gaga". A bit trickier when the presenter is a dialog box, but totally doable.

The way I would do is to define a application event (eg. LocationEvent<LocationHandler>) & handler encapsulating whatever data (ex. co ordinates) that you need to send and fire the event. First presenter fires the event when the mouse is clicked. Second Presenter handles the event and takes appropriate action.

how does the PlaceChange Event gets fired?? As of 2.1M2, PlaceController still isn't bound to History, so only PlaceController#goTo will fire first a PlaceChangeRequestedEvent (which can be rejected) and then (if the first hasn't been rejected by listeners) a PlaceChangeEvent.

he generally adopted way of doing things in GWT is to have custom events go through the event bus. In this case, you're talking about "navigation", so maybe the concept of "place" would be better than "just" some custom event. I encourage you to look at gwt-platform, gwt- presenter and other MVP frameworks for GWT, and/or look at the Activity concept from the upcoming GWT 2.1. Using actvities, you'd have an ActivityManager managing your "center". The tree would use the PlaceController.goTo to navigate to a new "place". An ActivityMapper (that you passed to the ActivityManager in the constructor) would map the place to an Activity (a presenter), and the ActivityManager will manage the current Activity for the display it manages, i.e.it will stop() the current activity if its ok (willStop returns true) and then only start the new Activity, which will call the Display back to show its view. The tree would probably also listen to PlaceChangeEvent on the event bus to update the selected item depending on the current place (in case some other component calls the PlaceController.goTo)

he generally adopted way of doing things in GWT is to have custom events go through the event bus. In this case, you're talking about "navigation", so maybe the concept of "place" would be better than "just" some custom event. I encourage you to look at gwt-platform, gwt- presenter and other MVP frameworks for GWT, and/or look at the Activity concept from the upcoming GWT 2.1.

Using actvities, you'd have an ActivityManager managing your "center". The tree would use the PlaceController.goTo to navigate to a new "place". An ActivityMapper (that you passed to the ActivityManager in the constructor) would map the place to an Activity (a presenter), and the ActivityManager will manage the current Activity for the display it manages, i.e.it will stop() the current activity if its ok (willStop returns true) and then only start the new Activity, which will call the Display back to show its view. The tree would probably also listen to PlaceChangeEvent on the event bus to update the selected item depending on the current place (in case some other component calls the PlaceController.goTo)

Start moving the code of addStock to the view. Try not to use widget code on the presenter. Then create an interface and implement in the presenter: class SomeViewHandlers {     void deleteStock(Stock code); } You already have the deleteStock method... so just add "implements SomeViewHandlers" to it. Then you need to give to the display that interface (generally in the constructor): display.setViewHandlers(this); Then in the presenter lease the method as: private void addStock(JsArray<Stock> stocks) { display.addStock(stocks); } And in the view copyPaste the code of the method and change this:  removeButton.addClickHandler(new ClickHandler() {        @Override        public void onClick(ClickEvent event) {          *viewHandlers.*deleteStock(code);        }      });