fixing the crashes and maybe speed up loading of objects in slides

TODO.org

@@ -12,13 +12,18 @@
 
 - [X] Initial ListView with text coming from =getLyricList=
 - [X] Depending on this [[*Need to make getLyricList give back the verses with empty lines as separate slides][Need to make getLyricList give back the verses with empty lines as separate slides]]
-- [ ] Need to perhaps address the MPV crashing problem for a smoother experience.
+- [X] Need to perhaps address the MPV crashing problem for a smoother experience.
+
   Essentially, mpv objects cause a seg fault when we remove them from the qml graph scene and are somehow re-referencing them. Using =reuseItems=, I can prevent the seg fault but then we are storing a lot of things in memory and will definitely cause slowdowns on older hardware. So far I haven't seen too many problems with the =reuseItems= piece yet.
 
   Apparently, I still have crashing
 
+  Setting a really high =cacheBuffer= in the ListView seems to have fixed the crashing, but will result in higher memory use. As of right now we are using 1.1Gb total, so I may think of a better solution later, but for now, that'll have to work.
+
 - [X] There is also a small hiccup in switching between songs. I appears as if songs that don't have any slides will have ghost slides from the previously selected song.
 
+- [ ] Another issue I discovered was that when switching to a song with videoBackgrounds, the mpv object doesn't ALWAYS load the first frame of the slide. Can I let the video play a tiny bit longer to make sure frames ALWAYS get loaded?
+
 ** WAIT Make toolbar functional for =songeditor= [3/4] [75%]           :core:
 [[file:~/dev/church-presenter/src/qml/presenter/SongEditor.qml::Controls.ToolBar {]]
 

src/qml/presenter/Slide.qml

@@ -93,7 +93,7 @@ Item {
 
         Timer {
             id: pauseTimer
-            interval: 200
+            interval: 300
             onTriggered: mpv.pause()
         }
 

src/qml/presenter/SlideEditor.qml

@@ -58,26 +58,28 @@ Item {
         anchors.rightMargin: 20
         model: songModel
         clip: true
-        cacheBuffer: 900
+        cacheBuffer: 1900
         reuseItems: true
         spacing: Kirigami.Units.gridUnit
-        /* flickDeceleration: 4000 */
-        /* boundsMovement: Flickable.StopAtBounds */
         synchronousDrag: true
-        delegate: Presenter.Slide {
-            id: representation
-            editMode: true
-            imageSource: root.imageBackground
-            videoSource: root.videoBackground
-            hTextAlignment: root.hTextAlignment
-            vTextAlignment: root.vTextAlignment
-            chosenFont: font
-            textSize: fontSize
-            preview: true
-            text: verse
-            implicitWidth: slideList.width
-            implicitHeight: width * 9 / 16
-            itemType: "song"
+        delegate: Loader {
+            width: slideList.width
+            height: width * 9 / 16
+            Presenter.Slide {
+                id: representation
+                editMode: true
+                imageSource: root.imageBackground
+                videoSource: root.videoBackground
+                hTextAlignment: root.hTextAlignment
+                vTextAlignment: root.vTextAlignment
+                chosenFont: font
+                textSize: fontSize
+                preview: true
+                text: verse
+                implicitWidth: slideList.width
+                implicitHeight: width * 9 / 16
+                itemType: "song"
+            }
         }
 
         Kirigami.WheelHandler {
@@ -155,9 +157,10 @@ Item {
     }
 
     function loadVideo() {
+        showPassiveNotification("I'm loading the videos");
         for (var i = 0; i < slideList.count; ++i) {
             slideList.currentIndex = i;
-            slideList.currentItem.loadVideo();
+            slideList.currentItem.representation.loadVideo();
             print(slideList.currentItem);
         }
     }

src/qml/presenter/SongEditor.qml

@@ -424,6 +424,7 @@ Item {
         /* print("Here are the verses: " + verses); */
         const verses = songsqlmodel.getLyricList(id);
         verses.forEach(slideEditor.appendVerse);
+        /* slideEditor.loadVideo(); */
     }
 
     function clearSlides() {