Add FloatingActionButtonBehavior sample

FAB.Sample/FAB.Sample.csproj

@@ -65,6 +65,7 @@
     <Compile Include="Adapter\LanguageAdapter.cs" />
     <Compile Include="SnackActivity.cs" />
     <Compile Include="FloatingActionMenuBehavior.cs" />
+    <Compile Include="FloatingActionButtonBehavior.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="Resources\AboutResources.txt" />

FAB.Sample/FloatingActionButtonBehavior.cs

@@ -0,0 +1,91 @@
+using System;
+using Android.Support.Design.Widget;
+using Android.Content;
+using Android.Util;
+using Clans.Fab;
+using Android.Views;
+using Android.Support.V4.View;
+using Android.Runtime;
+using FloatingActionButton = Clans.Fab.FloatingActionButton;
+
+namespace FAB.Demo
+{
+    [Register("FAB.Demo.FloatingActionButtonBehavior")]
+    public class FloatingActionButtonBehavior : CoordinatorLayout.Behavior
+    {
+        private float mTranslationY;
+
+        public FloatingActionButtonBehavior(Context context, IAttributeSet attrs)
+            : base(context, attrs)
+        {
+        }
+
+        public override bool LayoutDependsOn(CoordinatorLayout parent, Java.Lang.Object child, Android.Views.View dependency)
+        {
+            return IsInstanceOf<Snackbar.SnackbarLayout>(dependency);
+        }
+
+        public override bool OnDependentViewChanged(CoordinatorLayout parent, Java.Lang.Object child, Android.Views.View dependency)
+        {
+            if (IsInstanceOf<FloatingActionButton>(child) && IsInstanceOf<Snackbar.SnackbarLayout>(dependency))
+            {
+                this.UpdateTranslation(parent, (View)child, dependency);
+            }
+
+            return false;
+        }
+
+        public override void OnDependentViewRemoved(CoordinatorLayout parent, Java.Lang.Object child, View dependency)
+        {
+            if (IsInstanceOf<FloatingActionButton>(child) && IsInstanceOf<Snackbar.SnackbarLayout>(dependency))
+            {
+                this.UpdateTranslation(parent, (View)child, dependency);
+            }
+        }
+
+        private void UpdateTranslation(CoordinatorLayout parent, View child, View dependency)
+        {
+            float translationY = this.GetTranslationY(parent, child);
+            if (translationY != this.mTranslationY)
+            {
+                ViewCompat.Animate(child).Cancel();
+
+                if (Math.Abs(translationY - this.mTranslationY) == (float)dependency.Height)
+                {
+                    ViewCompat.Animate(child)
+                        .TranslationY(translationY)
+                        .SetListener((IViewPropertyAnimatorListener)null);
+                }
+                else
+                {
+                    ViewCompat.SetTranslationY(child, translationY);
+                }
+
+                this.mTranslationY = translationY;
+            }
+        }
+
+        private float GetTranslationY(CoordinatorLayout parent, View child)
+        {
+            float minOffset = 0.0F;
+            var dependencies = parent.GetDependencies(child);
+            int i = 0;
+
+            for (int z = dependencies.Count; i < z; ++i)
+            {
+                View view = (View)dependencies[i];
+                if (IsInstanceOf<Snackbar.SnackbarLayout>(view) && parent.DoViewsOverlap(child, view))
+                {
+                    minOffset = Math.Min(minOffset, ViewCompat.GetTranslationY(view) - (float)view.Height);
+                }
+            }
+
+            return minOffset;
+        }
+
+        private bool IsInstanceOf<T>(object instance)
+        {
+            return instance.GetType().IsAssignableFrom(typeof(T));
+        }
+    }
+}