diff --git a/csharp/Facebook.YogaKit/Facebook.YogaKit.Shared.shproj b/csharp/Facebook.YogaKit/Facebook.YogaKit.Shared.shproj
new file mode 100644
index 00000000..0943de36
--- /dev/null
+++ b/csharp/Facebook.YogaKit/Facebook.YogaKit.Shared.shproj
@@ -0,0 +1,11 @@
+
+
+
+ {A24B3BA6-3143-4FFF-B8B8-1EDF166F5F4A}
+
+
+
+
+
+
+
\ No newline at end of file
diff --git a/csharp/Facebook.YogaKit/Facebook.YogaKit.projitems b/csharp/Facebook.YogaKit/Facebook.YogaKit.projitems
new file mode 100644
index 00000000..abc6371b
--- /dev/null
+++ b/csharp/Facebook.YogaKit/Facebook.YogaKit.projitems
@@ -0,0 +1,15 @@
+
+
+
+ $(MSBuildAllProjects);$(MSBuildThisFileFullPath)
+ true
+ {A24B3BA6-3143-4FFF-B8B8-1EDF166F5F4A}
+
+
+ Facebook.YogaKit
+
+
+
+
+
+
\ No newline at end of file
diff --git a/csharp/Facebook.YogaKit/YogaKit.cs b/csharp/Facebook.YogaKit/YogaKit.cs
new file mode 100644
index 00000000..e5d06656
--- /dev/null
+++ b/csharp/Facebook.YogaKit/YogaKit.cs
@@ -0,0 +1,180 @@
+using System;
+using System.Collections.Generic;
+using Facebook.Yoga;
+#if __IOS__
+using NativeView = UIKit.UIView;
+#endif
+
+namespace Facebook.YogaKit
+{
+ public static class YogaKit
+ {
+ internal static Dictionary Bridges = new Dictionary();
+
+ public static void UsesYoga(this NativeView view, bool usesYoga)
+ {
+ YogaKitNative.UsesYoga(view, usesYoga);
+ }
+
+ public static bool GetUsesYoga(this NativeView view)
+ {
+ return YogaKitNative.GetUsesYoga(view);
+ }
+
+ public static void IncludeYogaLayout(this NativeView view, bool includeInLayout)
+ {
+ YogaKitNative.IncludeYogaLayout(view, includeInLayout);
+ }
+
+ public static bool GetIncludeYogaLayout(this NativeView view)
+ {
+ return YogaKitNative.GetIncludeYogaLayout(view);
+ }
+
+ public static void YogaWidth(this NativeView view, nfloat width)
+ {
+ var node = GetYogaNode(view);
+ node.Width = (float)width;
+ }
+
+ public static void YogaHeight(this NativeView view, nfloat height)
+ {
+ var node = GetYogaNode(view);
+ node.Height = (float)height;
+ }
+
+ public static void YogaMinWidth(this NativeView view, float minWidth)
+ {
+ var node = GetYogaNode(view);
+ node.MinWidth = minWidth;
+ }
+
+ public static void YogaMinHeight(this NativeView view, float minHeight)
+ {
+ var node = GetYogaNode(view);
+ node.MinHeight = minHeight;
+ }
+
+ public static void YogaMaxWidth(this NativeView view, float maxWidth)
+ {
+ var node = GetYogaNode(view);
+ node.MaxWidth = maxWidth;
+ }
+
+ public static void YogaMaxHeight(this NativeView view, float maxHeight)
+ {
+ var node = GetYogaNode(view);
+ node.MaxHeight = maxHeight;
+ }
+
+ public static void YogaAlignItems(this NativeView view, YogaAlign align)
+ {
+ var node = GetYogaNode(view);
+ node.AlignItems = align;
+ }
+
+ public static void YogaJustify(this NativeView view, YogaJustify justify)
+ {
+ var node = GetYogaNode(view);
+ node.JustifyContent = justify;
+ }
+
+ public static void YogaAlign(this NativeView view, YogaAlign align)
+ {
+ var node = GetYogaNode(view);
+ node.AlignContent = align;
+ }
+
+ public static void YogaAlignSelf(this NativeView view, YogaAlign align)
+ {
+ var node = GetYogaNode(view);
+ node.AlignSelf = align;
+ }
+
+ public static void YogaDirection(this NativeView view, YogaDirection direction)
+ {
+ var node = GetYogaNode(view);
+ node.StyleDirection = direction;
+ }
+
+ public static void YogaFlexDirection(this NativeView view, YogaFlexDirection direction)
+ {
+ var node = GetYogaNode(view);
+ node.FlexDirection = direction;
+ }
+
+ public static void YogaPositionType(this NativeView view, YogaPositionType position)
+ {
+ var node = GetYogaNode(view);
+ node.PositionType = position;
+ }
+
+ public static void YogaFlexWrap(this NativeView view, YogaWrap wrap)
+ {
+ var node = GetYogaNode(view);
+ node.Wrap = wrap;
+ }
+
+ public static void YogaFlexShrink(this NativeView view, float shrink)
+ {
+ var node = GetYogaNode(view);
+ node.FlexShrink = shrink;
+ }
+
+ public static void YogaFlexGrow(this NativeView view, float grow)
+ {
+ var node = GetYogaNode(view);
+ node.FlexGrow = grow;
+ }
+
+ public static void YogaFlexBasis(this NativeView view, float basis)
+ {
+ var node = GetYogaNode(view);
+ node.FlexBasis = basis;
+ }
+
+ public static void YogaPositionForEdge(this NativeView view, float position, YogaEdge edge)
+ {
+ var node = GetYogaNode(view);
+ node.SetPosition(edge, position);
+ }
+
+ public static void YogaMarginForEdge(this NativeView view, float margin, YogaEdge edge)
+ {
+ var node = GetYogaNode(view);
+ node.SetMargin(edge, margin);
+ }
+
+ public static void YogaPaddingForEdge(this NativeView view, float padding, YogaEdge edge)
+ {
+ var node = GetYogaNode(view);
+ node.SetPadding(edge, padding);
+ }
+
+ public static void YogaAspectRation(this NativeView view, float ratio)
+ {
+ var node = GetYogaNode(view);
+ node.StyleAspectRatio = ratio;
+ }
+
+ #region Layout and Sizing
+ public static void YogaApplyLayout(this NativeView view)
+ {
+ YogaKitNative.CalculateLayoutWithSize(view, view.Bounds.Size);
+ YogaKitNative.ApplyLayoutToViewHierarchy(view);
+ }
+
+ public static YogaDirection YogaResolvedDirection(this NativeView view)
+ {
+ var node = GetYogaNode(view);
+ return node.LayoutDirection;
+ }
+
+ #endregion
+
+ public static YogaNode GetYogaNode(this NativeView view)
+ {
+ return YogaKitNative.GetYogaNode(view);
+ }
+ }
+}
\ No newline at end of file
diff --git a/csharp/Facebook.YogaKit/YogaKitNative.cs b/csharp/Facebook.YogaKit/YogaKitNative.cs
new file mode 100644
index 00000000..fd872835
--- /dev/null
+++ b/csharp/Facebook.YogaKit/YogaKitNative.cs
@@ -0,0 +1,255 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using Facebook.Yoga;
+#if __IOS__
+using CoreGraphics;
+using Foundation;
+using UIKit;
+#endif
+
+namespace Facebook.YogaKit
+{
+ internal static class YogaKitNative
+ {
+ static NSString YogaNodeKey = new NSString("YogaNode");
+
+ static NSString UsesYogaKey = new NSString("UsesYoga");
+
+ static NSString IncludeYogaKey = new NSString("UsesYoga");
+
+ public static void UsesYoga(UIView view, bool usesYoga)
+ {
+ var value = NSNumber.FromBoolean(usesYoga);
+ objc_setAssociatedObject(view.Handle, UsesYogaKey.Handle, value.Handle, AssociationPolicy.RETAIN_NONATOMIC);
+ }
+
+ public static bool GetUsesYoga(UIView view)
+ {
+ var value = ObjCRuntime.Runtime.GetNSObject(objc_getAssociatedObject(view.Handle, UsesYogaKey.Handle)) as NSNumber;
+ return value == null ? false : value.BoolValue;
+ }
+
+ public static void IncludeYogaLayout(UIView view, bool includeInLayout)
+ {
+ var value = NSNumber.FromBoolean(includeInLayout);
+ objc_setAssociatedObject(view.Handle, IncludeYogaKey.Handle, value.Handle, AssociationPolicy.RETAIN_NONATOMIC);
+ }
+
+ public static bool GetIncludeYogaLayout(UIView view)
+ {
+ var value = ObjCRuntime.Runtime.GetNSObject(objc_getAssociatedObject(view.Handle, IncludeYogaKey.Handle)) as NSNumber;
+ return value == null ? true : value.BoolValue;
+ }
+
+ public static YogaNode GetYogaNode(UIView view)
+ {
+ var value = ObjCRuntime.Runtime.GetNSObject(objc_getAssociatedObject(view.Handle, YogaNodeKey.Handle)) as YGNodeBridge;
+ if (value == null)
+ {
+ value = new YGNodeBridge();
+ value.SetContext(view);
+ objc_setAssociatedObject(view.Handle, YogaNodeKey.Handle, value.Handle, AssociationPolicy.RETAIN_NONATOMIC);
+ }
+ return value.node;
+ }
+
+ public static CGSize CalculateLayoutWithSize(UIView view, CGSize size)
+ {
+ if (!view.GetUsesYoga())
+ {
+ System.Diagnostics.Debug.WriteLine("Doesn't use Yoga");
+ }
+ AttachNodesFromViewHierachy(view);
+ var node = GetYogaNode(view);
+
+ node.Width = (float)size.Width;
+ node.Height = (float)size.Height;
+ node.CalculateLayout();
+
+ return new CGSize { Width = node.LayoutWidth, Height = node.LayoutHeight };
+ }
+
+ public static void ApplyLayoutToViewHierarchy(UIView view)
+ {
+ if (!view.GetIncludeYogaLayout())
+ return;
+
+ var node = GetYogaNode(view);
+ CGPoint topLeft = new CGPoint(node.LayoutX, node.LayoutY);
+ CGPoint bottomRight = new CGPoint(topLeft.X + node.LayoutWidth, topLeft.Y + node.LayoutHeight);
+ view.Frame = new CGRect(RoundPixelValue(topLeft.X), RoundPixelValue(topLeft.Y), RoundPixelValue(bottomRight.X) - RoundPixelValue(topLeft.X), RoundPixelValue(bottomRight.Y) - RoundPixelValue(topLeft.Y));
+ bool isLeaf = !view.GetUsesYoga() || view.Subviews.Length == 0;
+ if (!isLeaf)
+ {
+ for (int i = 0; i < view.Subviews.Length; i++)
+ {
+ ApplyLayoutToViewHierarchy(view.Subviews[i]);
+ }
+ }
+ }
+
+ public static CGSize YogaIntrinsicSize(this UIView view)
+ {
+ var constrainedSize = new CGSize
+ {
+ Width = float.NaN,
+ Height = float.NaN
+ };
+ return CalculateLayoutWithSize(view, constrainedSize);
+ }
+
+ static YogaSize MeasureView(YogaNode node, float width, YogaMeasureMode widthMode, float height, YogaMeasureMode heightMode)
+ {
+ var constrainedWidth = (widthMode == YogaMeasureMode.Undefined) ? nfloat.MaxValue : width;
+ var constrainedHeight = (heightMode == YogaMeasureMode.Undefined) ? nfloat.MaxValue : height;
+
+ UIView view = null;
+ if (YogaKit.Bridges.ContainsKey(node))
+ (YogaKit.Bridges[node] as YGNodeBridge).viewRef.TryGetTarget(out view);
+
+ var sizeThatFits = view.SizeThatFits(new CGSize(constrainedWidth, constrainedHeight));
+
+ var finalWidth = SanitizeMeasurement(constrainedWidth, sizeThatFits.Width, widthMode);
+ var finalHeight = SanitizeMeasurement(constrainedHeight, sizeThatFits.Height, heightMode);
+
+ return MeasureOutput.Make(finalWidth, finalHeight);
+ }
+
+ static float SanitizeMeasurement(nfloat constrainedSize, nfloat measuredSize, YogaMeasureMode measureMode)
+ {
+ float result;
+ if (measureMode == YogaMeasureMode.Exactly)
+ {
+ result = (float)constrainedSize;
+ }
+ else if (measureMode == YogaMeasureMode.AtMost)
+ {
+ result = (float)Math.Min(constrainedSize, measuredSize);
+ }
+ else {
+ result = (float)measuredSize;
+ }
+
+ return result;
+
+ }
+
+ static double RoundPixelValue(nfloat value)
+ {
+ nfloat scale = UIScreen.MainScreen.Scale;
+
+ return Math.Round(value * scale) / scale;
+ }
+
+ static void AttachNodesFromViewHierachy(UIView view)
+ {
+ var node = GetYogaNode(view);
+
+ // Only leaf nodes should have a measure function
+ if (!view.GetUsesYoga() || view.Subviews.Length == 0)
+ {
+ node.SetMeasureFunction(MeasureView);
+ RemoveAllChildren(node);
+ }
+ else
+ {
+ node.SetMeasureFunction(null);
+ // Create a list of all the subviews that we are going to use for layout.
+ var subviewsToInclude = new List();
+ foreach (var subview in view.Subviews)
+ {
+ if (subview.GetIncludeYogaLayout())
+ {
+ subviewsToInclude.Add(subview);
+ }
+ }
+
+ var shouldReconstructChildList = false;
+ if (node.Count != subviewsToInclude.Count)
+ {
+ shouldReconstructChildList = true;
+ }
+ else
+ {
+ for (int i = 0; i < subviewsToInclude.Count; i++)
+ {
+ if (node[i] != GetYogaNode(subviewsToInclude[i]))
+ {
+ shouldReconstructChildList = true;
+ break;
+ }
+ }
+ }
+
+ if (shouldReconstructChildList)
+ {
+ RemoveAllChildren(node);
+
+ for (int i = 0; i < subviewsToInclude.Count; i++)
+ {
+ var subView = subviewsToInclude[i];
+ node.Insert(i, subView.GetYogaNode());
+ AttachNodesFromViewHierachy(subView);
+ }
+ }
+ }
+ }
+
+ static void RemoveAllChildren(YogaNode node)
+ {
+ if (node == null)
+ return;
+
+ while (node.Count > 0)
+ {
+ node.Clear();
+ }
+ }
+
+
+ [DllImport("/usr/lib/libobjc.dylib")]
+ static extern void objc_setAssociatedObject(IntPtr @object, IntPtr key, IntPtr value, AssociationPolicy policy);
+
+ [DllImport("/usr/lib/libobjc.dylib")]
+ static extern IntPtr objc_getAssociatedObject(IntPtr @object, IntPtr key);
+
+ enum AssociationPolicy
+ {
+ ASSIGN = 0,
+ RETAIN_NONATOMIC = 1,
+ COPY_NONATOMIC = 3,
+ RETAIN = 01401,
+ COPY = 01403,
+ }
+ }
+
+ class YGNodeBridge : NSObject
+ {
+ bool disposed;
+ internal WeakReference viewRef;
+ internal YogaNode node;
+ public YGNodeBridge()
+ {
+ node = new YogaNode();
+ }
+
+ public void SetContext(UIView view)
+ {
+ viewRef = new WeakReference(view);
+ YogaKit.Bridges.Add(node, this);
+ }
+
+ protected override void Dispose(bool disposing)
+ {
+ if (disposing && !disposed)
+ {
+ disposed = true;
+ YogaKit.Bridges.Remove(node);
+ viewRef = null;
+ node = null;
+ }
+ base.Dispose(disposing);
+ }
+ }
+}
\ No newline at end of file