package android.support.v4.app; import android.support.annotation.IdRes; import android.support.annotation.Nullable; import android.view.View; /** * Callbacks to a {@link Fragment}'s container. */ public abstract class FragmentContainer { /** * Return the view with the given resource ID. May return {@code null} if the * view is not a child of this container. */ @Nullable public abstract View onFindViewById(@IdRes int id); /** * Return {@code true} if the container holds any view. */ public abstract boolean onHasView(); }