public class NActivity extends Activity{

   protected void onCreate(Bundle savedInstanceState){

      setContentView(R.layout.activity_main);

      Button button=getInstances(R.id.button1);

      Button button2=getInstances(R.id.button2);

      TextView tv1=getInstances(R.id.textview1);

      TextView tv2=getInstances(R.id.textview2);

   }

   protected <T extends View> T getInstances(int id) {

        return (T) findViewById(id);

    }

}

原文地址http://www.oschina.net/code/snippet_2410256_51108