From fb7f7a25d33e3dfdfb07d26b7590f2af67d018ef Mon Sep 17 00:00:00 2001
From: Shane Neuville <shane94@hotmail.com>
Date: Wed, 24 Apr 2019 18:36:19 -0600
Subject: [PATCH] Shell hamburger (#5961)

* Draw the hamburger if the user hasn't supplied an icon

* move variable

* remove excess code

* remove public
---
 Xamarin.Forms.Platform.Android/PickerManager.cs    |   2 -
 .../Renderers/ShellPageRendererTracker.cs          |  50 +++++++++++++++++++--
 Xamarin.Forms.Platform.iOS/Resources/3bar.png      | Bin 205 -> 0 bytes
 Xamarin.Forms.Platform.iOS/Resources/3bar@2x.png   | Bin 263 -> 0 bytes
 .../Xamarin.Forms.Platform.iOS.csproj              |   6 ---
 5 files changed, 47 insertions(+), 11 deletions(-)
 delete mode 100644 Xamarin.Forms.Platform.iOS/Resources/3bar.png
 delete mode 100644 Xamarin.Forms.Platform.iOS/Resources/3bar@2x.png

diff --git a/Xamarin.Forms.Platform.Android/PickerManager.cs b/Xamarin.Forms.Platform.Android/PickerManager.cs
index 52fcd99..d200513 100644
--- a/Xamarin.Forms.Platform.Android/PickerManager.cs
+++ b/Xamarin.Forms.Platform.Android/PickerManager.cs
@@ -79,8 +79,6 @@ namespace Xamarin.Forms.Platform.Android
 						renderer1.OnClick();
 					else if (picker?.Parent?.Parent?.Parent is IPickerRenderer renderer2)
 						renderer2.OnClick();
-					else
-						throw new System.Exception("Renderer not found temp check for Shane things");
 				}
 			}
 		}
diff --git a/Xamarin.Forms.Platform.iOS/Renderers/ShellPageRendererTracker.cs b/Xamarin.Forms.Platform.iOS/Renderers/ShellPageRendererTracker.cs
index e5589d6..71befeb 100644
--- a/Xamarin.Forms.Platform.iOS/Renderers/ShellPageRendererTracker.cs
+++ b/Xamarin.Forms.Platform.iOS/Renderers/ShellPageRendererTracker.cs
@@ -1,4 +1,5 @@
 using CoreGraphics;
+using Foundation;
 using System;
 using System.Collections.Generic;
 using System.Collections.Specialized;
@@ -54,6 +55,7 @@ namespace Xamarin.Forms.Platform.iOS
 		UISearchController _searchController;
 		SearchHandler _searchHandler;
 		Page _page;
+		NSCache _nSCache;
 
 		BackButtonBehavior BackButtonBehavior { get; set; }
 		UINavigationItem NavigationItem { get; set; }
@@ -61,6 +63,7 @@ namespace Xamarin.Forms.Platform.iOS
 		public ShellPageRendererTracker(IShellContext context)
 		{
 			_context = context;
+			_nSCache = new NSCache();
 		}
 
 		public async void OnFlyoutBehaviorChanged(FlyoutBehavior behavior)
@@ -247,14 +250,55 @@ namespace Xamarin.Forms.Platform.iOS
 				}
 				item = item?.Parent;
 			}
-			if (image == null)
-				image = "3bar.png";
-			var icon = await image.GetNativeImageAsync();
+
+			UIImage icon = null;
+
+			if (image != null)
+				icon = await image.GetNativeImageAsync();
+			else
+				icon = DrawHamburger();
+			
+
 			var barButtonItem = new UIBarButtonItem(icon, UIBarButtonItemStyle.Plain, OnMenuButtonPressed);
+
 			barButtonItem.AccessibilityIdentifier = "OK";
 			NavigationItem.LeftBarButtonItem = barButtonItem;
 		}
 
+		UIImage DrawHamburger()
+		{
+			const string hamburgerKey = "Hamburger";
+			UIImage img = (UIImage)_nSCache.ObjectForKey((NSString)hamburgerKey);
+
+			if (img != null)
+				return img;
+
+			var rect = new CGRect(0, 0, 23f, 23f);
+
+			UIGraphics.BeginImageContextWithOptions(rect.Size, false, 0);
+			var ctx = UIGraphics.GetCurrentContext();
+			ctx.SaveState();
+			ctx.SetStrokeColor(UIColor.Blue.CGColor);
+
+			float size = 3f;
+			float start = 4f;
+			ctx.SetLineWidth(size);
+
+			for(int i = 0; i< 3; i++)
+			{
+				ctx.MoveTo(1f, start + i * (size * 2));
+				ctx.AddLineToPoint(22f, start + i * (size * 2));
+				ctx.StrokePath();
+			}
+
+			ctx.RestoreState();
+			img = UIGraphics.GetImageFromCurrentImageContext();
+			UIGraphics.EndImageContext();
+
+			_nSCache.SetObjectforKey(img, (NSString)hamburgerKey);
+			return img;
+		}
+
 		void OnMenuButtonPressed(object sender, EventArgs e)
 		{
 			_context.Shell.SetValueFromRenderer(Shell.FlyoutIsPresentedProperty, true);
diff --git a/Xamarin.Forms.Platform.iOS/Resources/3bar.png b/Xamarin.Forms.Platform.iOS/Resources/3bar.png
deleted file mode 100644
index 50d67714e9634c535f71c813221d05a432cbaf8d..0000000000000000000000000000000000000000
GIT binary patch
literal 0
HcmV?d00001

literal 205
zcmeAS@N?(olHy`uVBq!ia0vp^;vmey1|%P7U0DF67>k44ofy`glX(f`u%tWsIx;Y9
z?C1WI$O`0h7I;J!GcfQS24TkI`72U@f|4b!5hcO-X(i=}MX3x0iJ5sNdU>fO3MP66
zdPasH6*8v+71?^aIEHw5zdd8f#bChU9QeNe<rI<QefJMu;1^sTzCV4^ujJi%kL_L<
u73|@;!ye1lH@)%qg6KYf)2{q=uNe5c<vyG~_%;h@5QC?ypUXO@geCwuMncm7

diff --git a/Xamarin.Forms.Platform.iOS/Resources/3bar@2x.png b/Xamarin.Forms.Platform.iOS/Resources/3bar@2x.png
deleted file mode 100644
index 7693e4fc38dc7c24d4ae092b3707df611770a29d..0000000000000000000000000000000000000000
GIT binary patch
literal 0
HcmV?d00001

literal 263
zcmeAS@N?(olHy`uVBq!ia0vp^dLYcf1|-9GYMTQo#^NA%Cx&(BWL^R}Ea{HEjtmSN
z`?>!lvI6;>1s;*b3=DjSL74G){)!Z!pk#?_L`iUdT1k0gQ7S`0VrE{6US4X6f{C7i
zo{`~4h0LiyMdh9@jv*P&Z_gQWu^95O9Q^x#c`e&=*>3HC0HG3-`<Crf0w*BB59ewp
z$=c<%`+silHsXT8dprF%9bW$SL*~DNKsQGyJZSyhv+TzfS-Z3HdZ#o_AmESx=e{%F
Xf7ew!g`wgo&<PBlu6{1-oD!M<yT)2U

diff --git a/Xamarin.Forms.Platform.iOS/Xamarin.Forms.Platform.iOS.csproj b/Xamarin.Forms.Platform.iOS/Xamarin.Forms.Platform.iOS.csproj
index 49ccbaf..2c2e945 100644
--- a/Xamarin.Forms.Platform.iOS/Xamarin.Forms.Platform.iOS.csproj
+++ b/Xamarin.Forms.Platform.iOS/Xamarin.Forms.Platform.iOS.csproj
@@ -41,9 +41,6 @@
     <Reference Include="System.Net.Http" />
   </ItemGroup>
   <ItemGroup>
-    <BundleResource Include="Resources\3bar%402x.png" />
-  </ItemGroup>
-  <ItemGroup>
     <Compile Include="$(MSBuildThisFileDirectory)ContextActionCell.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)ContextScrollViewDelegate.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)GlobalCloseContextGestureRecognizer.cs" />
@@ -266,8 +263,5 @@
       <Link>Properties\GlobalAssemblyInfo.cs</Link>
     </Compile>
   </ItemGroup>
-  <ItemGroup>
-    <BundleResource Include="Resources\3bar.png" />
-  </ItemGroup>
   <ItemGroup />
 </Project>
\ No newline at end of file
-- 
2.7.4