Android: How can View as Observer cleverly treat variables from Observed Models?
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I want to implement an MVP-like pattern on my Android app, and in my own pattern, View is an Activity and it is notified by Models of their member variables being changed. 

**My abstract Model**.

    public abstract class Model extends Observable {}

**My implemented Model**. I add `notifyObservers()` to every `setBlah()` methods, even if it looks repetitive, since by doing so, I could easily prevent some variables that View doesn't need from being notified of. In this case, notDisplay is such variable. 

    public class ExModel extends Model {
        protected int i;
        protected String s;
        protected double notDisplay;

        public void setI(int i) {
	    	this.i = i;
	    	this.setChanged();                
	    	this.notifyObservers(i);
        }

	    public void setS(String s) {
	    	this.s = s;
	    	this.setChanged(); 
	    	this.notifyObservers(s);
	    }

	    public void setNotDisplay(double notDisplay) {
	    	this.notDisplay = notDisplay;
    	}

    }

**My Activity aka View**.

    public class AndroidMVPActivity extends Activity implements Observer {

        protected Presenter p;
        protected TextView txtI;
        protected TextView txtS;
        protected TextView txtD;

        public AndroidMVPActivity() {
		    // call a Presenter.
        }

        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            this.setContentView(R.layout.main);
            // I know within onCreate isn't the best place to findViews, 
            // and it should be an interface called by a Presenter.
            txtI = (TextView) this.findViewById(R.id.txtI);
            txtS = (TextView) this.findViewById(R.id.txtS);
            txtD = (TextView) this.findViewById(R.id.txtD);
        }

        @Override
        public void update(Observable observable, Object data) {
            // HERE IS WHERE MY ISSUE ARISES.
            // I want to write something like...
            // viewInstance.setText(observable.date);
            // but...
        }
    }


I guess my Presenter is omittable, unless we go in a more P-central MVP pattern (I mean, when Model is updated, it notifies Presenter which later notifies View). 

At least 99 percent of what I want to View do by the `update()` method is `TextView.setText()`, so the class I'd want to cast the Observable instance is clear. TextView, that is. But how could we specify instances? (in this case, how to refer to txtI or txtS?). Is there any clever way?