public class MResource {

	public static int getIdByName(Context context, String className, String name) {

		String packageName = context.getPackageName();

		Class r = null;

		int id = 0;

		try {

			r = Class.forName(packageName + ".R");

			Class[] classes = r.getClasses();

			Class desireClass = null;

			for (int i = 0; i < classes.length; ++i) {

				if (classes[i].getName().split("\\$")[1].equals(className)) {

					desireClass = classes[i];

					break;

				}

			}

			if (desireClass != null)

				id = desireClass.getField(name).getInt(desireClass);

		} catch (ClassNotFoundException e) {

			e.printStackTrace();

		} catch (IllegalArgumentException e) {

			e.printStackTrace();

		} catch (SecurityException e) {

			e.printStackTrace();

		} catch (IllegalAccessException e) {

			e.printStackTrace();

		} catch (NoSuchFieldException e) {

			e.printStackTrace();

		}

		return id;

	}

}

setContentView(MResource.getIdByName(getApplication(), "layout", "layout_main"));