Add collection transition events

Author: Edvinas01

CHANGELOG.md

@@ -11,7 +11,7 @@ Minor UX updates and bug fixes.
 - More logging which shows that a scene is being currently loaded.
 - Methods to access in `loadingCollection` and `loadedCollection` in `ScriptableSceneController`.
 - Exposed `IsLoading` property in `ScriptableSceneController`.
-- Events in `BaseScriptableSceneTransition`.
+- Events which are fired when transitions are entered and exited.
 
 ### Changed
 - Updated Scene Manager Window to support reordering and to provide more info.

Runtime/Events/CollectionEventHandler.cs

@@ -32,6 +32,18 @@ internal sealed class CollectionEventHandler : ICollectionEventHandler
         private UnityEvent<CollectionUnloadEventArgs> onUnloadExited =
             new UnityEvent<CollectionUnloadEventArgs>();
 
+        [SerializeField]
+        private UnityEvent onShowTransitionEntered = new UnityEvent();
+
+        [SerializeField]
+        private UnityEvent onShowTransitionExited = new UnityEvent();
+
+        [SerializeField]
+        private UnityEvent onHideTransitionEntered = new UnityEvent();
+
+        [SerializeField]
+        private UnityEvent onHideTransitionExited = new UnityEvent();
+
         #endregion
 
         #region Public Events
@@ -46,6 +58,14 @@ internal sealed class CollectionEventHandler : ICollectionEventHandler
 
         public event CollectionUnloadEvent OnUnloadExited;
 
+        public event CollectionTransitionEvent OnShowTransitionEntered;
+
+        public event CollectionTransitionEvent OnShowTransitionExited;
+
+        public event CollectionTransitionEvent OnHideTransitionEntered;
+
+        public event CollectionTransitionEvent OnHideTransitionExited;
+
         #endregion
 
         #region Internal Methods
@@ -156,6 +176,59 @@ internal void RaiseUnloadExited(CollectionUnloadEventArgs args)
             }
         }
 
+        // TODO: these events below are not tested
+        internal void RaiseShowTransitionEntered()
+        {
+            try
+            {
+                onShowTransitionEntered.Invoke();
+                OnShowTransitionEntered?.Invoke();
+            }
+            catch (Exception exception)
+            {
+                Debug.LogError(exception);
+            }
+        }
+
+        internal void RaiseShowTransitionExited()
+        {
+            try
+            {
+                onShowTransitionExited.Invoke();
+                OnShowTransitionExited?.Invoke();
+            }
+            catch (Exception exception)
+            {
+                Debug.LogError(exception);
+            }
+        }
+
+        internal void RaiseHideTransitionEntered()
+        {
+            try
+            {
+                onHideTransitionEntered.Invoke();
+                OnHideTransitionEntered?.Invoke();
+            }
+            catch (Exception exception)
+            {
+                Debug.LogError(exception);
+            }
+        }
+
+        internal void RaiseHideTransitionExited()
+        {
+            try
+            {
+                onHideTransitionExited.Invoke();
+                OnHideTransitionExited?.Invoke();
+            }
+            catch (Exception exception)
+            {
+                Debug.LogError(exception);
+            }
+        }
+
         #endregion
     }
 }

Runtime/Events/CollectionEventHandlerDelegates.cs

@@ -14,4 +14,10 @@
     /// Invoked when <see cref="BaseScriptableSceneCollection"/> starts to unload or is unloaded.
     /// </summary>
     public delegate void CollectionUnloadEvent(CollectionUnloadEventArgs args);
+
+    /// <summary>
+    /// Invoked when <see cref="BaseScriptableSceneCollection"/> starts to show or hides the
+    /// transition.
+    /// </summary>
+    public delegate void CollectionTransitionEvent(); // TODO: add args
 }

Runtime/Events/ICollectionEventHandler.cs

@@ -29,6 +29,26 @@ public interface ICollectionEventHandler
         /// </summary>
         public event CollectionUnloadEvent OnUnloadExited;
 
+        /// <summary>
+        /// Called when transition of <see cref="BaseScriptableSceneCollection"/> starts to show.
+        /// </summary>
+        public event CollectionTransitionEvent OnShowTransitionEntered;
+
+        /// <summary>
+        /// Called when transition of <see cref="BaseScriptableSceneCollection"/> is shown.
+        /// </summary>
+        public event CollectionTransitionEvent OnShowTransitionExited;
+
+        /// <summary>
+        /// Called when transition of <see cref="BaseScriptableSceneCollection"/> starts to hide.
+        /// </summary>
+        public event CollectionTransitionEvent OnHideTransitionEntered;
+
+        /// <summary>
+        /// Called when transition of <see cref="BaseScriptableSceneCollection"/> is hidden.
+        /// </summary>
+        public event CollectionTransitionEvent OnHideTransitionExited;
+
         #endregion
     }
 }

Runtime/ScriptableSceneCollection.cs

@@ -97,15 +97,19 @@ public override IEnumerator ShowTransitionRoutine()
         {
             if (transition)
             {
+                collectionEvents.RaiseShowTransitionEntered();
                 yield return transition.ShowRoutine();
+                collectionEvents.RaiseShowTransitionExited();
             }
         }
 
         public override IEnumerator HideTransitionRoutine()
         {
             if (transition)
             {
+                collectionEvents.RaiseHideTransitionEntered();
                 yield return transition.HideRoutine();
+                collectionEvents.RaiseHideTransitionExited();
             }
         }
 

Runtime/Utilities/ScriptableSceneUtilities.cs

@@ -180,6 +180,10 @@ CollectionEventHandler otherHandler
             handler.OnLoadProgress += otherHandler.RaiseLoadProgress;
             handler.OnUnloadEntered += otherHandler.RaiseUnloadEntered;
             handler.OnUnloadExited += otherHandler.RaiseUnloadExited;
+            handler.OnShowTransitionEntered += otherHandler.RaiseShowTransitionEntered;
+            handler.OnShowTransitionExited += otherHandler.RaiseShowTransitionExited;
+            handler.OnHideTransitionEntered += otherHandler.RaiseHideTransitionEntered;
+            handler.OnHideTransitionExited += otherHandler.RaiseHideTransitionExited;
         }
 
         // TODO: how can we avoid this?
@@ -193,6 +197,10 @@ CollectionEventHandler otherHandler
             handler.OnLoadProgress -= otherHandler.RaiseLoadProgress;
             handler.OnUnloadEntered -= otherHandler.RaiseUnloadEntered;
             handler.OnUnloadExited -= otherHandler.RaiseUnloadExited;
+            handler.OnShowTransitionEntered -= otherHandler.RaiseShowTransitionEntered;
+            handler.OnShowTransitionExited -= otherHandler.RaiseShowTransitionExited;
+            handler.OnHideTransitionEntered -= otherHandler.RaiseHideTransitionEntered;
+            handler.OnHideTransitionExited -= otherHandler.RaiseHideTransitionExited;
         }
 
         // TODO: how can we avoid this?