From a74923b7b29a63a3fd0da7aa27ca8c09e6a72a2f Mon Sep 17 00:00:00 2001
From: David Ask <david@formbound.com>
Date: Thu, 23 Aug 2018 21:32:20 +0200
Subject: [PATCH] Add support for forwarding container view controller methods

---
 Framework/StateViewController.h   |  2 --
 Sources/StateViewController.swift | 29 +++++++++++++++++++++++++++++
 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/Framework/StateViewController.h b/Framework/StateViewController.h
index a26f28b..8dc96a9 100644
--- a/Framework/StateViewController.h
+++ b/Framework/StateViewController.h
@@ -5,5 +5,3 @@ FOUNDATION_EXPORT double StateViewControllerVersionNumber;
 
 //! Project version string for StateViewController.
 FOUNDATION_EXPORT const unsigned char StateViewControllerVersionString[];
-
-// In this header, you should import all the public headers of your framework using statements like #import <StateViewController/PublicHeader.h>
diff --git a/Sources/StateViewController.swift b/Sources/StateViewController.swift
index a58acae..85a6dd6 100644
--- a/Sources/StateViewController.swift
+++ b/Sources/StateViewController.swift
@@ -249,6 +249,26 @@ open class StateViewController<State: Equatable>: UIViewController {
         endStateTransitionIfNeeded(animated: animated)
     }
 
+    // MARK: - Container view controller forwarding
+
+    open override var childViewControllerForStatusBarStyle: UIViewController? {
+        return childViewControllers.last
+    }
+
+    open override var childViewControllerForStatusBarHidden: UIViewController? {
+        return childViewControllers.last
+    }
+
+    @available(iOS 11, *)
+    open override func childViewControllerForScreenEdgesDeferringSystemGestures() -> UIViewController? {
+        return childViewControllers.last
+    }
+
+    @available(iOS 11, *)
+    open override func childViewControllerForHomeIndicatorAutoHidden() -> UIViewController? {
+        return childViewControllers.last
+    }
+
     // MARK: - State transitioning
 
     /// Indicates whether the view controller currently is transitioning between states.
@@ -530,6 +550,15 @@ fileprivate extension StateViewController {
             addContentViewController(viewController, animated: animated)
         }
 
+        if adding.isEmpty == false || removing.isEmpty == false {
+            setNeedsStatusBarAppearanceUpdate()
+
+            if #available(iOS 11, *) {
+                setNeedsUpdateOfHomeIndicatorAutoHidden()
+                setNeedsUpdateOfScreenEdgesDeferringSystemGestures()
+            }
+        }
+
         // Update the hierarchy of the view controllers that will represent the state being transitioned to.
         updateHierarchy(of: next)
         return true