Implement correct reset functionality to clear display when closing c…

…urrent file or opening a new one. This fixes Bug #7

explorer/src/main/java/io/github/jmcleodfoss/explorer/BlockBTreeDisplay.java

@@ -7,16 +7,27 @@
 @SuppressWarnings("serial")
 class BlockBTreeDisplay extends BTreeWithData
 {
+	/** The current block's contents */
+	private BlockDescriptionDisplay blockDescriptionDisplay;
+
 	/**	Construct a BTreeWithData object with the appropriate orientation and contents for the block B-tree display. */
 	BlockBTreeDisplay()
 	{
 		super(JSplitPane.HORIZONTAL_SPLIT);
-		setDataView(new BlockDescriptionDisplay(tree));
+		blockDescriptionDisplay = new BlockDescriptionDisplay(tree);
+		setDataView(blockDescriptionDisplay);
 	}
 
 	/**	Get the tree model for the block B-tree. */
 	TreeModel treeModel()
 	{
 		return (TreeModel)pstExplorer.pst().blockBTree;
 	}
+
+	/**	Clear the tree model. */
+	void reset()
+	{
+		super.reset();
+		blockDescriptionDisplay.reset();
+	}
 }

explorer/src/main/java/io/github/jmcleodfoss/explorer/NodeBTreeDisplay.java

@@ -11,11 +11,15 @@
 @SuppressWarnings("serial")
 class NodeBTreeDisplay extends BTreeWithData
 {
+	/** The current node's contents */
+	private NodeDescriptionDisplay nodeDescriptionDisplay;
+
 	/**	Construct a BTreeWithData object with the given orientation and content pane. */
 	protected NodeBTreeDisplay(JFrame parentFrame)
 	{
 		super(JSplitPane.HORIZONTAL_SPLIT);
-		setDataView(new NodeDescriptionDisplay(tree, parentFrame));
+		nodeDescriptionDisplay = new NodeDescriptionDisplay(tree, parentFrame);
+		setDataView(nodeDescriptionDisplay);
 	}
 
 	/**	Update the views when a new file is read in.
@@ -29,4 +33,11 @@ public void fileLoaded(final PST pst)
 			tree.setModel(treeModel());
 		}
 	}
+
+	/**	Clear the tree model. */
+	void reset()
+	{
+		super.reset();
+		nodeDescriptionDisplay.reset();
+	}
 }