Java tutorial
//package com.java2s; //License from project: Apache License import android.app.Activity; import android.support.annotation.IdRes; import android.view.View; import android.view.Window; public class Main { public static View getRootView(Window w) { return w.findViewById(android.R.id.content).getRootView(); } public static <T extends View> T findViewById(Activity activity, @IdRes int id) { T v = (T) activity.findViewById(id); return v; } public static <T extends View> T findViewById(View parent, int id) { T v = (T) parent.findViewById(id); return v; } }