Cleanup ContentPlayerViewController

PlayWallPlugins/PlayWallPluginContentPlayer/src/main/scala/de/tobias/playpad/plugin/content/ContentPlayerViewController.scala

@@ -87,15 +87,16 @@ class ContentPlayerViewController extends NVC {
 	}
 
 	def configurePlayers(configuration: PlayerInstanceConfiguration): Unit = {
+		val parent = getParent.asInstanceOf[Pane]
+		parent.getChildren.clear()
+
 		mediaPlayers.clear()
 		configuration.instances.forEach(player => {
-			mediaPlayers.addOne(new MediaPlayerStack(player))
+			val mediaPlayerStack = new MediaPlayerStack(player)
+			mediaPlayers.addOne(mediaPlayerStack)
+			parent.getChildren.add(mediaPlayerStack)
 		})
 
-		val parent = getParent.asInstanceOf[Pane]
-		parent.getChildren.clear()
-		mediaPlayers.foreach(player => parent.getChildren.add(player))
-
 		getStageContainer.ifPresent(container => {
 			val stage = container.getStage