Hello everyone,

I've got another question concerning MVC with a drag and drop interface. Let me recapitulate what I have so far:

I've got an MVC triad managing a simple JFrame in which mouse clicks create coloured dots. In the mouseListener in the controller a mouse click is translated into creating a new triad of MVC objects that represent an individual dot. The model of the dot is stored in a vector, which is managed in the model of the application.

So, in essence, two levels of MVC.

My next problem is how to delete a dot model from the vector. In the dot-level controller I have a mouseListener. How do I reach the vector in the application-level model? Do I have to create a local variable to store a reference to the application model, or is it enough to store a reference to the vector.

And how do I do that? It's not enough to try something that kind of works; I want to do this the proper OO way.

Here is part of the code of the application-level model where the vector is created:

public class ColouredDotsAppModel
  private Vector<DotModel> chain;
  // Constructor
  public ColouredDotsAppModel()
    chain = new Vector<DotModel>();

And here is the overridden mouseReleased method in the dot-level controller. The first part of the method is to change the status of the dot (and by that way its color) when it is left-clicked upon without being dragged. The deleting should be done in the second part, when clicked on with the right mouse button.

  public void mouseReleased(MouseEvent mE)
    // If left mouse button clicked and released...
    if (!beenDragged)
      if ((mE.getModifiers() & InputEvent.BUTTON1_MASK) == InputEvent.BUTTON1_MASK)
        if(dotModel.getStatus() == 1)
        else if(dotModel.getStatus() == 2)
        else if(dotModel.getStatus() == 3)
      if ((mE.getModifiers() & InputEvent.BUTTON3_MASK) == InputEvent.BUTTON3_MASK)
        // TODO: remove dot from vector and from UI
    beenDragged = false;

If it is too confusing, I can upload my latest working project to an online storage. Just let me know.

Thanks in advance,