Add metnods for NSCoding/NSCopying

Headers/AppKit/NSSplitViewController.h

@@ -37,7 +37,7 @@ extern "C" {
 
 @class NSSplitView, NSSplitViewItem, NSArray, NSMutableArray;
   
-@interface NSSplitViewController : NSViewController
+@interface NSSplitViewController : NSViewController <NSCoding, NSCopying>
 {
   NSSplitView *_splitView;
   CGFloat _minimumThicknessForInlineSidebars;

Headers/AppKit/NSSplitViewItem.h

@@ -62,7 +62,7 @@ typedef NSInteger NSTitlebarSeparatorStyle;
 
 @class NSViewController;
   
-@interface NSSplitViewItem : NSObject
+@interface NSSplitViewItem : NSObject <NSCoding, NSCopying>
 {
   CGFloat _automaticMaximumThickness;
   CGFloat _preferredThicknessFraction;
@@ -82,9 +82,13 @@ typedef NSInteger NSTitlebarSeparatorStyle;
 + (instancetype)splitViewItemWithViewController:(NSViewController *)viewController;
 
 - (CGFloat) automaticMaximumThickness;
+- (void) setAutomaticMaximumThickness: (CGFloat)f;
 - (CGFloat) preferredThicknessFraction;
+- (void) setPreferredThicknessFraction: (CGFloat)f;
 - (CGFloat) minimumThickness;
+- (void) setMinimumThickness: (CGFloat)f;
 - (CGFloat) maximumThickness;
+- (void) setMaximumThickness: (CGFloat)f;
 
 - (/* NSLayoutPriority */ CGFloat) holdingPriority;
 

Source/NSSplitViewItem.m

@@ -25,19 +25,29 @@
 #import "AppKit/NSSplitViewItem.h"
 
 @implementation NSSplitViewItem
-+ (instancetype)contentListWithViewController: (NSViewController *)viewController
+- (instancetype) initWithViewController: (NSViewController *)viewController
 {
-  return nil;
+  self = [super init];
+  if (self != nil)
+    {
+      ASSIGN(_viewController, viewController);
+    }
+  return self;
 }
 
-+ (instancetype)sidebarWithViewController: (NSViewController *)viewController
++ (instancetype) contentListWithViewController: (NSViewController *)viewController
 {
-  return nil;
+  return [[NSSplitViewItem alloc] initWithViewController: viewController];
 }
 
-+ (instancetype)splitViewItemWithViewController: (NSViewController *)viewController
++ (instancetype) sidebarWithViewController: (NSViewController *)viewController
 {
-  return nil;
+  return [[NSSplitViewItem alloc] initWithViewController: viewController];
+}
+
++ (instancetype) splitViewItemWithViewController: (NSViewController *)viewController
+{
+  return [[NSSplitViewItem alloc] initWithViewController: viewController];  
 }
 
 - (CGFloat) automaticMaximumThickness
@@ -134,4 +144,20 @@
 {
   return _viewController;
 }
+
+// NSCoding
+- (instancetype) initWithCoder: (NSCoder *)coder
+{
+  return self;
+}
+
+- (void) encodeWithCoder: (NSCoder *)coder
+{
+}
+
+// NSCopying
+- (id) copyWithZone: (NSZone *)z
+{
+  return nil;
+}
 @end