MVC vs MVP - Part 1
Davy 18 Feb 2011MVC or MVP everyone have heard those acronym at least once. But what they exactly stand for ?
MVC is Model View Controller and MVP is Model View Presenter. I can see some of you saying “what a scam” they changed one word and voilà. It’s a little more complex than this. Let’s start with some diagrams
As you can see, the communication between each entity isn’t identical. I will try to explain this difference.
MVC
The view
In the MVC design pattern, the view know the model and can display it.
public class MyView {
private Model model;
private void populateView(Model model)
{
final String name = model.getName();
this.label.setText(name);
}
}The view listens the model an will be aware if it changes.
public class MyView implements ModelListener{
public void onModelChanged()
{
//Update the view with the new status of the model
}
}The controller
The controller knows the view and listens event from it.
public class MyController implements ViewListener {
public void onButtonClicked()
{
final String name = view.getName();
view.displayPopup(name);
}
}The controller can modify the model without updating the view, because the view is a model listener.
public class MyController implements ViewListener {
public void onButtonClicked()
{
final String name = view.getName();
model.setName(name);
}
}MVP
The view
In the MVP design pattern, the view doesn’t know the model and receives basic orders to populate the interface (setLabelText, setTodayDate, but never read value from the model)
public class MyView {
public void setNameValue(String name)
{
this.label.setText(name);
}
}The presenter
The presenter knows the view, populates the view and binds itself to interface listeners
public class MyPresenter {
private View view;
private Model model;
public void bind()
{
this.view.addButtonActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent event) {
this.view.setText("blabla");
}
});
}
public void populateView()
{
this.view.setName(model.getName());
this.view.setButtonEnabled(true);
}
}The presenter is the only entity to know the model and to listen it.
public class MyPresenter implements ModelListener{
private Model model;
public void onModelChanged()
{
this.view.setName(model.getName());
}
}To be continued…
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