From c3693a01cc1d6aa7cb692e92b46ed7298fcdfaae Mon Sep 17 00:00:00 2001
From: artyom <worldbeater-dev@yandex.ru>
Date: Fri, 2 Oct 2020 00:28:13 +0300
Subject: [PATCH] Ability to set easings

---
 ...ansition.cs => CompositePageTransition.cs} | 10 ++---
 src/Avalonia.Visuals/Animation/CrossFade.cs   | 29 ++++++++----
 src/Avalonia.Visuals/Animation/PageSlide.cs   | 44 +++++++++----------
 3 files changed, 47 insertions(+), 36 deletions(-)
 rename src/Avalonia.Visuals/Animation/{CompositeTransition.cs => CompositePageTransition.cs} (85%)

diff --git a/src/Avalonia.Visuals/Animation/CompositeTransition.cs b/src/Avalonia.Visuals/Animation/CompositePageTransition.cs
similarity index 85%
rename from src/Avalonia.Visuals/Animation/CompositeTransition.cs
rename to src/Avalonia.Visuals/Animation/CompositePageTransition.cs
index 62ed9d5bc1..46bbb0bed2 100644
--- a/src/Avalonia.Visuals/Animation/CompositeTransition.cs
+++ b/src/Avalonia.Visuals/Animation/CompositePageTransition.cs
@@ -6,28 +6,28 @@ using Avalonia.Metadata;
 namespace Avalonia.Animation
 {
     /// <summary>
-    /// Defines a composite transition that can be used to combine multiple transitions into one.
+    /// Defines a composite page transition that can be used to combine multiple transitions.
     /// </summary>
     /// <remarks>
     /// <para>
-    /// Instantiate the <see cref="CompositeTransition" /> in XAML and initialize the
+    /// Instantiate the <see cref="CompositePageTransition" /> in XAML and initialize the
     /// <see cref="Transitions" /> property in order to have many animations triggered at once.
     /// For example, you can combine <see cref="CrossFade"/> and <see cref="PageSlide"/>.
     /// <code>
     /// <![CDATA[
     /// <reactiveUi:RoutedViewHost Router="{Binding Router}">
     ///   <reactiveUi:RoutedViewHost.PageTransition>
-    ///     <CompositeTransition>
+    ///     <CompositePageTransition>
     ///       <PageSlide Duration="0.5" />
     ///       <CrossFade Duration="0.5" />
-    ///     </CompositeTransition>
+    ///     </CompositePageTransition>
     ///   </reactiveUi:RoutedViewHost.PageTransition>
     /// </reactiveUi:RoutedViewHost>
     /// ]]>
     /// </code>
     /// </para>
     /// </remarks>
-    public class CompositeTransition : IPageTransition
+    public class CompositePageTransition : IPageTransition
     {
         /// <summary>
         /// Gets or sets the transitions to be executed. Can be defined from XAML.
diff --git a/src/Avalonia.Visuals/Animation/CrossFade.cs b/src/Avalonia.Visuals/Animation/CrossFade.cs
index 640f401418..2ba9f6aeba 100644
--- a/src/Avalonia.Visuals/Animation/CrossFade.cs
+++ b/src/Avalonia.Visuals/Animation/CrossFade.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Avalonia.Animation.Easings;
 using Avalonia.Styling;
 using Avalonia.VisualTree;
 
@@ -74,14 +75,26 @@ namespace Avalonia.Animation
         /// </summary>
         public TimeSpan Duration
         {
-            get
-            {
-                return _fadeOutAnimation.Duration;
-            }
-            set
-            {
-                _fadeOutAnimation.Duration = _fadeInAnimation.Duration = value;
-            }
+            get => _fadeOutAnimation.Duration;
+            set => _fadeOutAnimation.Duration = _fadeInAnimation.Duration = value;
+        }
+
+        /// <summary>
+        /// Gets or sets element entrance easing.
+        /// </summary>
+        public Easing EntranceEasing
+        {
+            get => _fadeInAnimation.Easing;
+            set => _fadeInAnimation.Easing = value;
+        }
+
+        /// <summary>
+        /// Gets or sets element exit easing.
+        /// </summary>
+        public Easing ExitEasing
+        {
+            get => _fadeOutAnimation.Easing;
+            set => _fadeOutAnimation.Easing = value;
         }
 
         /// <summary>
diff --git a/src/Avalonia.Visuals/Animation/PageSlide.cs b/src/Avalonia.Visuals/Animation/PageSlide.cs
index 501c8c0ba4..b545385ad6 100644
--- a/src/Avalonia.Visuals/Animation/PageSlide.cs
+++ b/src/Avalonia.Visuals/Animation/PageSlide.cs
@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
+using Avalonia.Animation.Easings;
 using Avalonia.Media;
 using Avalonia.Styling;
 using Avalonia.VisualTree;
@@ -48,6 +49,16 @@ namespace Avalonia.Animation
         /// Gets the duration of the animation.
         /// </summary>
         public SlideAxis Orientation { get; set; }
+        
+        /// <summary>
+        /// Gets or sets element entrance easing.
+        /// </summary>
+        public Easing EntranceEasing { get; set; } = new LinearEasing();
+        
+        /// <summary>
+        /// Gets or sets element exit easing.
+        /// </summary>
+        public Easing ExitEasing { get; set; } = new LinearEasing();
 
         /// <summary>
         /// Starts the animation.
@@ -75,18 +86,12 @@ namespace Avalonia.Animation
             {
                 var animation = new Animation
                 {
-                    Children = 
+                    Easing = ExitEasing,
+                    Children =
                     {
                         new KeyFrame
                         {
-                            Setters =
-                            {
-                                new Setter
-                                {
-                                    Property = translateProperty,
-                                Value = 0d
-                                }
-                            },
+                            Setters = { new Setter { Property = translateProperty, Value = 0d } },
                             Cue = new Cue(0d)
                         },
                         new KeyFrame
@@ -100,10 +105,10 @@ namespace Avalonia.Animation
                                 }
                             },
                             Cue = new Cue(1d)
-                        }                       
-                    }
+                        }
+                    },
+                    Duration = Duration
                 };
-                animation.Duration = Duration;
                 tasks.Add(animation.RunAsync(from));
             }
 
@@ -112,9 +117,9 @@ namespace Avalonia.Animation
                 to.IsVisible = true;
                 var animation = new Animation
                 {
+                    Easing = EntranceEasing,
                     Children =
                     {
-
                         new KeyFrame
                         {
                             Setters =
@@ -129,19 +134,12 @@ namespace Avalonia.Animation
                         },
                         new KeyFrame
                         {
-                            Setters =
-                            {
-                                new Setter
-                                {
-                                    Property = translateProperty,
-                                    Value = 0d
-                                }
-                            },
+                            Setters = { new Setter { Property = translateProperty, Value = 0d } },
                             Cue = new Cue(1d)
                         }
-                    }
+                    },
+                    Duration = Duration
                 };
-                animation.Duration = Duration;
                 tasks.Add(animation.RunAsync(to));
             }