[NUI] Fix Navigator's animation and Page's visible state

Previously, Navigator's animation did not keep the final state.
e.g. Opacity from 1 to 0 animation did not keep opacity 0 when the
     animation was finished.
Now, Navigator's animation keeps the final state.

Previously, hidden Pages did not have actually hidden visibilities.
e.g. When the peek Page was hidden by newly pushed Page, the hidden
     Page's visible state was true.
Now, hidden Pages have actually hidden visibilities.

diff --git a/src/Tizen.NUI.Components/Controls/Navigation/Navigator.cs b/src/Tizen.NUI.Components/Controls/Navigation/Navigator.cs
index a896756..f161114 100755 (executable)
--- a/src/Tizen.NUI.Components/Controls/Navigation/Navigator.cs
+++ b/src/Tizen.NUI.Components/Controls/Navigation/Navigator.cs
@@ -253,31 +253,24 @@ namespace Tizen.NUI.Components
             curTop.InvokeDisappearing();
 
             //TODO: The following transition codes will be replaced with view transition.
-            if (curAnimation)
-            {
-                curAnimation.Stop();
-                curAnimation.Clear();
-            }
-
-            if (newAnimation)
-            {
-                newAnimation.Stop();
-                newAnimation.Clear();
-            }
+            InitializeAnimation();
 
             if (page is DialogPage == false)
             {
                 curAnimation = new Animation(1000);
                 curAnimation.AnimateTo(curTop, "Opacity", 0.0f, 0, 1000);
-                curAnimation.EndAction = Animation.EndActions.Discard;
+                curAnimation.EndAction = Animation.EndActions.StopFinal;
+                curAnimation.Finished += (object sender, EventArgs args) =>
+                {
+                    curTop.SetVisible(false);
+                };
                 curAnimation.Play();
 
-                using (var opacityProp = new Tizen.NUI.PropertyValue(0.0f))
-                {
-                    Tizen.NUI.Object.SetProperty(page.SwigCPtr, Page.Property.OPACITY, opacityProp);
-                }
+                page.Opacity = 0.0f;
+                page.SetVisible(true);
                 newAnimation = new Animation(1000);
                 newAnimation.AnimateTo(page, "Opacity", 1.0f, 0, 1000);
+                newAnimation.EndAction = Animation.EndActions.StopFinal;
                 newAnimation.Play();
             }
         }
@@ -316,35 +309,26 @@ namespace Tizen.NUI.Components
             curTop.InvokeDisappearing();
 
             //TODO: The following transition codes will be replaced with view transition.
-            if (curAnimation)
-            {
-                curAnimation.Stop();
-                curAnimation.Clear();
-            }
-
-            if (newAnimation)
-            {
-                newAnimation.Stop();
-                newAnimation.Clear();
-            }
+            InitializeAnimation();
 
             if (curTop is DialogPage == false)
             {
                 curAnimation = new Animation(1000);
                 curAnimation.AnimateTo(curTop, "Opacity", 0.0f, 0, 1000);
-                curAnimation.Play();
+                curAnimation.EndAction = Animation.EndActions.StopFinal;
                 curAnimation.Finished += (object sender, EventArgs e) =>
                 {
                     //Removes the current top page after transition is finished.
                     Remove(curTop);
+                    curTop.Opacity = 1.0f;
                 };
+                curAnimation.Play();
 
-                using (var opacityProp = new Tizen.NUI.PropertyValue(0.0f))
-                {
-                    Tizen.NUI.Object.SetProperty(newTop.SwigCPtr, Page.Property.OPACITY, opacityProp);
-                }
+                newTop.Opacity = 0.0f;
+                newTop.SetVisible(true);
                 newAnimation = new Animation(1000);
                 newAnimation.AnimateTo(newTop, "Opacity", 1.0f, 0, 1000);
+                newAnimation.EndAction = Animation.EndActions.StopFinal;
                 newAnimation.Play();
             }
             else
@@ -427,6 +411,20 @@ namespace Tizen.NUI.Components
             //Duplicate page is not pushed.
             if (navigationPages.Contains(page)) return;
 
+            //TODO: The following transition codes will be replaced with view transition.
+            InitializeAnimation();
+
+            if (index == PageCount)
+            {
+                page.Opacity = 1.0f;
+                page.SetVisible(true);
+            }
+            else
+            {
+                page.SetVisible(false);
+                page.Opacity = 0.0f;
+            }
+
             navigationPages.Insert(index, page);
             Add(page);
             page.Navigator = this;
@@ -479,6 +477,15 @@ namespace Tizen.NUI.Components
                 throw new ArgumentNullException(nameof(page), "page should not be null.");
             }
 
+            //TODO: The following transition codes will be replaced with view transition.
+            InitializeAnimation();
+
+            if ((page == Peek()) && (PageCount >= 2))
+            {
+                navigationPages[PageCount - 2].Opacity = 1.0f;
+                navigationPages[PageCount - 2].SetVisible(true);
+            }
+
             page.Navigator = null;
             navigationPages.Remove(page);
             base.Remove(page);
@@ -681,5 +688,23 @@ namespace Tizen.NUI.Components
         {
             TransitionFinished?.Invoke(this, new EventArgs());
         }
+
+        //TODO: The following transition codes will be replaced with view transition.
+        private void InitializeAnimation()
+        {
+            if (curAnimation != null)
+            {
+                curAnimation.Stop();
+                curAnimation.Clear();
+                curAnimation = null;
+            }
+
+            if (newAnimation != null)
+            {
+                newAnimation.Stop();
+                newAnimation.Clear();
+                newAnimation = null;
+            }
+        }
     }
 }