Question

I have an application with several graphs and tables on it.

I worked fast and just made classes like Graph and Table that each contained a request object (pseudo-code):

class Graph {
  private request;

  public function setDateRange(dateRange) {
    request.setDateRange(dateRange);
  }
  public function refresh() {
    request.getData(function() {
      //refresh the display
    });
  }
}

Upon a GUI event (say, someone changes the date range dropdown), I’d just call the setters on the Graph instance and then refresh it. Well, when I added other GUI elements like tables and whatnot, they all basically had similar methods (setDateRange and other things common to the request).

What are some more elegant OOP ways of doing this?

The application is very simple and I don’t want to over-architect it, but I also don’t want to have a bunch of classes with basically the same methods that are just routing to a request object. I also don’t want to set up each GUI class as inheriting from the request class, but I’m open to any ideas really.

Answer 1

As you commented the methods are identical. In that case I would suggest the following approach.

abstract class AbstractGUIElement {

    protected request;

    public function setDateRange(dateRange) {
        request.setDateRange(dateRange);
    }

    abstract function refresh();
}

Refreshing would probably be element specific so I have added it as an abstract method the inheriting types have to implement.

class Graph extends AbstractGUIElement {

    public function refresh() {
        // Graph specific refreshing
    }
}