Merge pull request #76 from thomaslevesque/fix-resume-on-show

Don't resume on show if animation was paused
XamlAnimatedGif · Mar 8, 2020 · 510aba1 · 510aba1
2 parents 3672cd6 + 9aed565
commit 510aba1
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Showing 2 changed files with 29 additions and 12 deletions.
diff --git a/WpfAnimatedGif/ImageAnimationController.cs b/WpfAnimatedGif/ImageAnimationController.cs
@@ -37,6 +37,7 @@ internal ImageAnimationController(Image image, ObjectAnimationUsingKeyFrames ani
 
             _image.ApplyAnimationClock(Image.SourceProperty, _clock);
 
+            IsPaused = !autoStart;
             if (autoStart)
                 _clockController.Resume();
         }
@@ -75,10 +76,7 @@ public TimeSpan Duration
         /// <summary>
         /// Returns a value that indicates whether the animation is paused.
         /// </summary>
-        public bool IsPaused
-        {
-            get { return _clock.IsPaused; }
-        }
+        public bool IsPaused { get; private set; }
 
         /// <summary>
         /// Returns a value that indicates whether the animation is complete.
@@ -122,6 +120,7 @@ public int CurrentFrame
         /// </summary>
         public void Pause()
         {
+            IsPaused = true;
             _clockController.Pause();
         }
 
@@ -130,7 +129,30 @@ public void Pause()
         /// </summary>
         public void Play()
         {
-            _clockController.Resume();
+            IsPaused = false;
+            if (!_isSuspended)
+                _clockController.Resume();
+        }
+
+        private bool _isSuspended;
+        internal void SetSuspended(bool isSuspended)
+        {
+            if (isSuspended == _isSuspended)
+                return;
+
+            bool wasSuspended = _isSuspended;
+            _isSuspended = isSuspended;
+            if (wasSuspended)
+            {
+                if (!IsPaused)
+                {
+                    _clockController.Resume();
+                }
+            }
+            else
+            {
+                _clockController.Pause();
+            }
         }
 
         /// <summary>

diff --git a/WpfAnimatedGif/ImageBehavior.cs b/WpfAnimatedGif/ImageBehavior.cs
@@ -382,13 +382,8 @@ private static void VisibilityChanged(object sender, DependencyPropertyChangedEv
                 var controller = GetAnimationController(img);
                 if (controller != null)
                 {
-                    if ((bool)e.NewValue)
-                    {
-                        controller.GotoFrame(0);
-                        controller.Play();
-                    }
-                    else
-                        controller.Pause();
+                    bool isVisible = (bool)e.NewValue;
+                    controller.SetSuspended(!isVisible);
                 }
             }
         }