JourneyMVPLoader_Presenter.java

class MyPresenter {
    private MyViewInterface viewInterface;
    private DataManager dataManager;
    private MyState state;
    
    MyPresenter(DataManager dataManager) {
        this.dataManager = dataManager;
        /* Initiates state with a default value for the initial UI 
           of this view */
        state = new MyState("This is the template data");
    }
    
    /**
     * Called when the UI became visible in onResume, thus we   
       save the interface object and update the UI with the cached 
       state */
    void attachView(MyViewInterface viewInterface) {
        this.viewInterface = viewInterface;
        viewInterface.updateUI(state);
    }
    
    /**
     * Called when the UI became invisible, thus we set the
       interface object to null as we can't dispatch more UI 
       updates but we keep our state object up to date with 
       the model changes and will update the UI when it attaches
       again. */
    void detachView() {
        this.viewInterface = null;
    }
    
    /* Button click UI event from submitButton in view to save   
       data in the model which we do using dataManager */
    void saveName(String name) {
        dataManager.saveName(name);
        state.setNameSaved(name);
        viewInterface.updateUI(state);
    }
}