FragmentUtils.java

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;

public class FragmentUtils {
	/**
	 * @param frag
	 *            The Fragment whose parent is to be found
	 * @param callbackInterface
	 *            The interface class that the parent should implement
	 * @return The parent of frag that implements the callbackInterface or null
	 *         if no such parent can be found
	 */
	@SuppressWarnings("unchecked") // Casts are checked using runtime methods
	public static <T> T getParent(Fragment frag, Class<T> callbackInterface) {
		Fragment parentFragment = frag.getParentFragment();
		if (parentFragment != null
				&& callbackInterface.isInstance(parentFragment)) {
			return (T) parentFragment;
		} else {
			FragmentActivity activity = frag.getActivity();
			if (activity != null && callbackInterface.isInstance(activity)) {
				return (T) activity;
			}
		}
		return null;
	}
}