From e43550c0393512afea3cfa41d4cfb0a108ba0bd1 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <slouken@libsdl.org>
Date: Sun, 9 Jun 2019 14:08:18 -0700
Subject: [PATCH] Fixed bug 4658 - iOS 12 fullscreen flag and
 SDL_HINT_IOS_HIDE_HOME_INDICATOR not working

Caleb Cornett

On iOS 12, creating a window with the SDL_WINDOW_FULLSCREEN flag does not dim the home indicator or defer system gestures. The same goes for setting the SDL_HINT_IOS_HIDE_HOME_INDICATOR to "2" -- it has no effect at all.

I've tracked down the source of this misbehavior to a timing issue. The initial `setNeedsUpdate...` calls were happening too early and getting applied to the launch screen by mistake. In the attached patch, I've added a call to those functions right after the launch screen is hidden so that they apply to the main view controller instead. This appears to fix the issue, at least on my iPhone 6s Plus.
---
 src/video/uikit/SDL_uikitappdelegate.m |  1 +
 src/video/uikit/SDL_uikitmessagebox.m  | 14 +-------------
 src/video/uikit/SDL_uikitvideo.h       |  2 ++
 src/video/uikit/SDL_uikitvideo.m       | 18 ++++++++++++++++++
 4 files changed, 22 insertions(+), 13 deletions(-)

diff --git a/src/video/uikit/SDL_uikitappdelegate.m b/src/video/uikit/SDL_uikitappdelegate.m
index 8d3e3c433..ecc695d25 100644
--- a/src/video/uikit/SDL_uikitappdelegate.m
+++ b/src/video/uikit/SDL_uikitappdelegate.m
@@ -343,6 +343,7 @@ SDL_LoadLaunchImageNamed(NSString *name, int screenh)
         window.alpha = 0.0;
     } completion:^(BOOL finished) {
         window.hidden = YES;
+        UIKit_ForceUpdateHomeIndicator(); /* Wait for launch screen to hide so settings are applied to the actual view controller. */
     }];
 }
 
diff --git a/src/video/uikit/SDL_uikitmessagebox.m b/src/video/uikit/SDL_uikitmessagebox.m
index 16a0c2122..b14a3c019 100644
--- a/src/video/uikit/SDL_uikitmessagebox.m
+++ b/src/video/uikit/SDL_uikitmessagebox.m
@@ -108,19 +108,7 @@ UIKit_ShowMessageBoxAlertController(const SDL_MessageBoxData *messageboxdata, in
         alertwindow.hidden = YES;
     }
 
-#if !TARGET_OS_TV
-    /* Force the main SDL window to re-evaluate home indicator state */
-    SDL_Window *focus = SDL_GetFocusWindow();
-    if (focus) {
-        SDL_WindowData *data = (__bridge SDL_WindowData *) focus->driverdata;
-        if (data != nil) {
-            if (@available(iOS 11.0, *)) {
-                [data.viewcontroller performSelectorOnMainThread:@selector(setNeedsUpdateOfHomeIndicatorAutoHidden) withObject:nil waitUntilDone:NO];
-                [data.viewcontroller performSelectorOnMainThread:@selector(setNeedsUpdateOfScreenEdgesDeferringSystemGestures) withObject:nil waitUntilDone:NO];
-            }
-        }
-    }
-#endif /* !TARGET_OS_TV */
+    UIKit_ForceUpdateHomeIndicator();
 
     *buttonid = messageboxdata->buttons[clickedindex].buttonid;
     return YES;
diff --git a/src/video/uikit/SDL_uikitvideo.h b/src/video/uikit/SDL_uikitvideo.h
index c43ed80b8..4e12855c1 100644
--- a/src/video/uikit/SDL_uikitvideo.h
+++ b/src/video/uikit/SDL_uikitvideo.h
@@ -39,6 +39,8 @@ CGRect UIKit_ComputeViewFrame(SDL_Window *window, UIScreen *screen);
 
 void UIKit_SuspendScreenSaver(_THIS);
 
+void UIKit_ForceUpdateHomeIndicator(void);
+
 SDL_bool UIKit_IsSystemVersionAtLeast(double version);
 
 #endif /* SDL_uikitvideo_h_ */
diff --git a/src/video/uikit/SDL_uikitvideo.m b/src/video/uikit/SDL_uikitvideo.m
index f0103aecc..7c21d16c2 100644
--- a/src/video/uikit/SDL_uikitvideo.m
+++ b/src/video/uikit/SDL_uikitvideo.m
@@ -221,6 +221,24 @@ UIKit_ComputeViewFrame(SDL_Window *window, UIScreen *screen)
     return frame;
 }
 
+void
+UIKit_ForceUpdateHomeIndicator()
+{
+#if !TARGET_OS_TV
+    /* Force the main SDL window to re-evaluate home indicator state */
+    SDL_Window *focus = SDL_GetFocusWindow();
+    if (focus) {
+        SDL_WindowData *data = (__bridge SDL_WindowData *) focus->driverdata;
+        if (data != nil) {
+            if (@available(iOS 11.0, *)) {
+                [data.viewcontroller performSelectorOnMainThread:@selector(setNeedsUpdateOfHomeIndicatorAutoHidden) withObject:nil waitUntilDone:NO];
+                [data.viewcontroller performSelectorOnMainThread:@selector(setNeedsUpdateOfScreenEdgesDeferringSystemGestures) withObject:nil waitUntilDone:NO];
+            }
+        }
+    }
+#endif /* !TARGET_OS_TV */
+}
+
 /*
  * iOS log support.
  *