Add Aspect Ratio extension method

Cirrious.FluentLayout/AdvancedFluentLayoutExtensions.cs

@@ -57,7 +57,10 @@ public static FluentLayout Above(this UIView view, UIView previous, nfloat? marg
         view.Bottom().EqualTo().TopOf(previous).Minus(margin.GetValueOrDefault(DefaultMargin));
 
     public static FluentLayout WithSameLeft(this UIView view, UIView previous) => view.Left().EqualTo().LeftOf(previous);
-
+
+	  public static FluentLayout WithAspectRatio(this UIView view, nfloat ratio) =>
+        view.Width().EqualTo().HeightOf(view).WithMultiplier(ratio);
+
     public static FluentLayout WithSameTop(this UIView view, UIView previous) => view.Top().EqualTo().TopOf(previous);
 
     public static FluentLayout WithSameCenterX(this UIView view, UIView previous) => view.CenterX().EqualTo().CenterXOf(previous);

QuickLayout.Core/ViewModels/AspectRatioViewModel.cs

@@ -0,0 +1,9 @@
+using MvvmCross.ViewModels;
+
+namespace QuickLayout.Core.ViewModels
+{
+    public class AspectRatioViewModel : MvxViewModel
+    {
+
+    }
+}

QuickLayout.Core/ViewModels/FirstViewModel.cs

@@ -35,5 +35,7 @@ public FirstViewModel(IMvxLogProvider logProvider, IMvxNavigationService navigat
         public void GoViewWithSafeArea() => NavigationService.Navigate<ViewWithSafeAreaViewModel>();
 
         public void GoCenterConstraints() => NavigationService.Navigate<ToCenterConstraintsViewModel>();
+
+        public void GoViewAspectRatio() => NavigationService.Navigate<AspectRatioViewModel>();
     }
 }

QuickLayout.Touch/QuickLayout.Touch.csproj

@@ -88,6 +88,7 @@
     <Compile Include="LinkerPleaseInclude.cs" />
     <Compile Include="Main.cs" />
     <Compile Include="AppDelegate.cs" />
+    <Compile Include="Views\AspectRatioView.cs" />
     <Compile Include="Views\ToCenterConstraintsView.cs" />
     <Compile Include="Views\DetailsView.cs" />
     <Compile Include="Views\FirstView.cs" />

QuickLayout.Touch/Views/AspectRatioView.cs

@@ -0,0 +1,56 @@
+using System;
+using Cirrious.FluentLayouts.Touch;
+using MvvmCross.Platforms.Ios.Views;
+using QuickLayout.Core.ViewModels;
+using UIKit;
+
+namespace QuickLayout.Touch.Views
+{
+    public class AspectRatioView : MvxViewController<AspectRatioViewModel>
+    {
+        public override void ViewDidLoad()
+        {
+            View.BackgroundColor = UIColor.Black;
+
+            var firstView = new UIView()
+            {
+                BackgroundColor = UIColor.Red,
+                Alpha = 0.5f
+            };
+            var secondView = new UIView()
+            {
+                BackgroundColor = UIColor.Blue,
+                Alpha = 0.5f
+            };
+            var thirdView = new UIView()
+            {
+                BackgroundColor = UIColor.Yellow
+            };
+
+            View.AddSubviews(firstView, secondView, thirdView);
+            View.SubviewsDoNotTranslateAutoresizingMaskIntoConstraints();
+
+            const float length = 200f;
+            const float padding = 32f;
+
+            View.AddConstraints(new FluentLayout[]
+            {
+                firstView.WithSameCenterX(View),
+                firstView.WithSameCenterY(View),
+                secondView.WithSameCenterX(View),
+                secondView.WithSameCenterY(View),
+                thirdView.WithSameCenterX(View),
+                thirdView.WithSameCenterY(View),
+
+                firstView.Height().EqualTo(length),
+                firstView.WithAspectRatio(1f/2f), // height is 2x larger than width
+
+                secondView.Width().EqualTo().HeightOf(firstView),
+                secondView.WithAspectRatio(2f/1f), // width is 2x larger than height
+
+                thirdView.Width().EqualTo().WidthOf(firstView).Minus(padding),
+                thirdView.WithAspectRatio(1f), // width and height are equal (force to be square)
+            });
+        }
+    }
+}

QuickLayout.Touch/Views/FirstView.cs

@@ -13,7 +13,7 @@ namespace QuickLayout.Touch.Views
     [MvxRootPresentation(WrapInNavigationController = true)]
     public class FirstView : MvxViewController
     {
-		private UIButton _viewForm, _viewFormGrid, _viewDetails, _viewSearch, _viewTip, _viewUpdateConstaints, _viewAdvancedVerticalStack, _fullSize, _directionFormView, _rightToLeft, _viewSafeArea, _viewCenterConstraints;
+		private UIButton _viewForm, _viewFormGrid, _viewDetails, _viewSearch, _viewTip, _viewUpdateConstaints, _viewAdvancedVerticalStack, _fullSize, _directionFormView, _rightToLeft, _viewSafeArea, _viewCenterConstraints, _viewAspectRatio;
 
         public override void ViewDidLoad()
         {
@@ -71,6 +71,10 @@ public override void ViewDidLoad()
             _viewCenterConstraints = new UIButton(UIButtonType.RoundedRect);
             _viewCenterConstraints.SetTitle("View Contraining to centers", UIControlState.Normal);
             Add(_viewCenterConstraints);
+
+            _viewAspectRatio = new UIButton(UIButtonType.RoundedRect);
+            _viewAspectRatio.SetTitle("Aspect Ratio", UIControlState.Normal);
+            Add(_viewAspectRatio);
 
 			View.SubviewsDoNotTranslateAutoresizingMaskIntoConstraints();
 
@@ -87,6 +91,7 @@ public override void ViewDidLoad()
             set.Bind(_rightToLeft).To("GoRightToLeft");
             set.Bind(_viewSafeArea).To("GoViewWithSafeArea");
             set.Bind(_viewCenterConstraints).To("GoCenterConstraints");
+            set.Bind(_viewAspectRatio).To("GoViewAspectRatio");
             set.Apply();
 
             var constraints = View.VerticalStackPanelConstraints(