[gnome-subtitles] Fix #166 - Opening an audio file after a video file shows the last frame played from that video

[Pedro Castro <pcastro src gnome org>]

commit b08c2c97489b274ab63d5c8f01f27e3275b60ad9
Author: Pedro Castro <pedro gnomesubtitles org>
Date:   Sat Jan 30 20:53:06 2021 +0000

    Fix #166 - Opening an audio file after a video file shows the last frame
    played from that video

 src/GnomeSubtitles/Ui/VideoPreview/Player.cs | 72 ++++++++++++----------------
 src/GnomeSubtitles/Ui/VideoPreview/Video.cs  | 11 +++--
 2 files changed, 38 insertions(+), 45 deletions(-)
---
diff --git a/src/GnomeSubtitles/Ui/VideoPreview/Player.cs b/src/GnomeSubtitles/Ui/VideoPreview/Player.cs
index d39e47b..d3611f2 100644
--- a/src/GnomeSubtitles/Ui/VideoPreview/Player.cs
+++ b/src/GnomeSubtitles/Ui/VideoPreview/Player.cs
@@ -1,6 +1,6 @@
 /*
  * This file is part of Gnome Subtitles.
- * Copyright (C) 2007-2019 Pedro Castro
+ * Copyright (C) 2007-2021 Pedro Castro
  *
  * Gnome Subtitles is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -21,8 +21,8 @@ using GnomeSubtitles.Ui.VideoPreview.Exceptions;
 using GStreamer;
 using Gtk;
 using SubLib.Core.Domain;
-using System;
 using SubLib.Util;
+using System;
 
 namespace GnomeSubtitles.Ui.VideoPreview {
 
@@ -33,7 +33,6 @@ public delegate void VideoDurationEventHandler (TimeSpan duration);
 public class Player {
 
        private AspectFrame frame = null;
-       //private Socket socket = null;
        private Playbin playbin = null;
        private PlayerPositionWatcher position = null;
        private bool hasFoundDuration = false;
@@ -50,9 +49,7 @@ public class Player {
        public Player (AspectFrame aspectFrame) {
                this.frame = aspectFrame;
 
-               //InitializeSocket();
                InitializePositionWatcher();
-               InitializePlaybin();
        }
        
 
@@ -70,18 +67,10 @@ public class Player {
                get { return playbin.CurrentStatus; }
        }
 
-       public bool HasDuration {
-               get { return playbin.Duration != TimeSpan.Zero; }
-       }
-
        public TimeSpan Duration {
                get { return playbin.Duration; }
        }
 
-       public bool HasVideoInfo {
-               get { return videoInfo != null; }
-       }
-
        public float AspectRatio {
                get { return videoInfo.AspectRatio; }
        }
@@ -105,20 +94,26 @@ public class Player {
        public float Speed {
                get { return speed; }
        }
-
+       
+       public bool IsLoadComplete {
+               get { return (playbin.CurrentStatus != MediaStatus.Unloaded) && HasVideoInfo() && 
HasDuration(); }
+       }
+       
 
        /* Public methods */
 
        public void Open (Uri videoUri) {
                this.videoUri = videoUri;
 
-               /* Load the playbin */
+               InitializePlaybin();
                playbin.Load(videoUri.AbsoluteUri);
        }
 
        public void Close () {
                position.Stop();
+               
                playbin.Unload();
+               DisposePlaybin();
 
                videoUri = null;
                hasFoundDuration = false;
@@ -171,35 +166,16 @@ public class Player {
                playbin.Seek(newPosition, speed); // newPosition in milliseconds
        }
 
-       public void Dispose () {
-               Close();
-               playbin.Dispose();
-       }
-
 
        /* Private members */
 
-
-       //private void InitializeSocket () {
-       //      socket = new Socket();
-
-       //      /* Set the socket background color. If we don't do this, the socket/video
-       //       * area will show a copy of the UI elements (menu, labels, other
-       //       * components) when the video isn't loaded.
-       //       */
-       //      RGBA black = new RGBA();
-       //      black.Red = 0;
-       //      black.Green = 0;
-       //      black.Blue = 0;
-       //      black.Alpha = 1;
-       //      socket.OverrideBackgroundColor(StateFlags.Normal, black);
-       //      socket.DoubleBuffered = false;
-
-       //      frame.Child = socket;
-
-       //      socket.Realize();
-       //      socket.Show();
-       //}
+       private bool HasDuration() {
+               return playbin.Duration != TimeSpan.Zero;
+       }
+       
+       public bool HasVideoInfo() {
+               return videoInfo != null;
+       }
 
        private void InitializePlaybin () {
                playbin = new Playbin();
@@ -223,7 +199,21 @@ public class Player {
                playbin.FoundVideoInfo += OnPlaybinFoundVideoInfo;
                playbin.FoundTag += OnPlaybinFoundTag;
        }
+       
+       private void DisposePlaybin () {
+               playbin.Error -= OnPlaybinError;
+               playbin.EndOfStream -= OnPlaybinEndOfStream;
+               playbin.StateChanged -= OnPlaybinStateChanged;
+               playbin.FoundVideoInfo -= OnPlaybinFoundVideoInfo;
+               playbin.FoundTag -= OnPlaybinFoundTag;
+               
+               Widget videoWidget = playbin.GetVideoWidget();
+               frame.Remove(videoWidget);
 
+               playbin.Dispose();
+               playbin = null;
+       }
+       
        private void InitializePositionWatcher () {
                position = new PlayerPositionWatcher(GetPosition);
                position.PositionPulse += OnPositionWatcherPulse;
diff --git a/src/GnomeSubtitles/Ui/VideoPreview/Video.cs b/src/GnomeSubtitles/Ui/VideoPreview/Video.cs
index 246658d..9d3f057 100644
--- a/src/GnomeSubtitles/Ui/VideoPreview/Video.cs
+++ b/src/GnomeSubtitles/Ui/VideoPreview/Video.cs
@@ -1,6 +1,6 @@
 /*
  * This file is part of Gnome Subtitles.
- * Copyright (C) 2006-2019 Pedro Castro
+ * Copyright (C) 2006-2021 Pedro Castro
  *
  * Gnome Subtitles is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -73,7 +73,7 @@ public class Video {
        }
 
        public bool IsStatePlaying {
-               get { return player.State == MediaStatus.Playing; }
+               get { return isLoaded && player.State == MediaStatus.Playing; }
        }
 
        public float FrameRate {
@@ -134,7 +134,9 @@ public class Video {
        }
 
        public void Quit () {
-               player.Dispose();
+               if (isLoaded) {
+                       player.Close();
+               }
        }
 
        public void SetLoopSelectionPlayback (bool enabled){
@@ -292,9 +294,10 @@ public class Video {
        }
 
        private bool IsPlayerLoadComplete () {
-               return (player != null) && (player.State != MediaStatus.Unloaded) && (player.HasVideoInfo) && 
(player.HasDuration);
+               return (player != null) && player.IsLoadComplete;
        }
 
+
        /* Event members */
 
        private void OnBaseInitFinished () {