Allow dropping multiple files in PadContentFactory implementation of ContentDragOption

PlayWallCore/src/main/java/de/tobias/playpad/pad/Pad.java

@@ -372,6 +372,7 @@ public class Pad {
 	}
 
 	public void removePath(MediaPath path) {
+		getContent().unloadMedia(path);
 		mediaPaths.remove(path);
 	}
 
@@ -382,6 +383,12 @@ public class Pad {
 		}
 	}
 
+	public void clearPaths() {
+		while (!mediaPaths.isEmpty()) {
+			removePath(mediaPaths.get(0));
+		}
+	}
+
 	/**
 	 * Get the status of the pad.
 	 *

PlayWallCore/src/main/java/de/tobias/playpad/pad/content/PadContentFactory.java

@@ -61,6 +61,13 @@ public abstract class PadContentFactory extends Component implements ContentDrag
 			currentPad.getController().getView().showBusyView(true);
 		}
 
+		if (currentPad.getContent() instanceof Playlistable) {
+			currentPad.clearPaths();
+			for (File file : files) {
+				currentPad.addPath(file.toPath());
+			}
+		} else {
 			currentPad.setPath(files.get(0).toPath());
 		}
 	}
+}