Fix for preview panel not showing in Ubuntu 11.04 with OpenJDK

src/replicatorg/app/ui/MainWindow.java

@@ -205,8 +205,7 @@ public class MainWindow extends JFrame implements MRJAboutHandler, MRJQuitHandle
 
 	MainButtonPanel buttons;
 
-	CardLayout cardLayout = new CardLayout();
-	JPanel cardPanel = new JPanel(cardLayout);
+	protected final MainWindowCardPanel cardPanel = new MainWindowCardPanel();
 	EditorHeader header = new EditorHeader(this);
 	{
 		header.setChangeListener(this);
@@ -355,10 +354,10 @@ public void windowClosing(WindowEvent e) {
 		console = new MessagePanel(this);
 		console.setBorder(null);
 
-		splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT, cardPanel,
+		splitPane = new JSplitPane(JSplitPane.VERTICAL_SPLIT, cardPanel.getPanel(),
 				console);
 
-		new FileDrop( null, cardPanel, /*dragBorder,*/ new FileDrop.Listener()
+		new FileDrop( null, cardPanel.getPanel(), /*dragBorder,*/ new FileDrop.Listener()
 		{   public void filesDropped( java.io.File[] files )
 		{   
 			// for( java.io.File file : files )
@@ -3365,11 +3364,10 @@ public void toolStatusChanged(MachineToolStatusEvent event) {
 	public void setCurrentElement(BuildElement e) {
 		currentElement = e;
 		if (currentElement != null) {
-			CardLayout cl = (CardLayout)cardPanel.getLayout();
 			if (currentElement.getType() == BuildElement.Type.MODEL ) {
-				cl.show(cardPanel, MODEL_TAB_KEY);
+				cardPanel.show(MODEL_TAB_KEY);
 			} else {
-				cl.show(cardPanel, GCODE_TAB_KEY);
+				cardPanel.show(GCODE_TAB_KEY);
 			}
 
 		}

src/replicatorg/app/ui/MainWindowCardPanel.java

@@ -0,0 +1,87 @@
+package replicatorg.app.ui;
+
+import java.awt.CardLayout;
+import java.awt.Component;
+import java.util.HashMap;
+
+import javax.swing.JPanel;
+
+import replicatorg.app.Base;
+
+/**
+ * This class is a workaround for a problem with OpenJDK and Java3D on Ubuntu 11.04, 
+ * where the preview window wouldn't show up when there are two cards in the JPanel
+ * with a CardLayout. To work around that, this will store the widgets in componentMap
+ * instead, and only add them to the JPanel when it's time to show them.  
+ * 
+ * Since this issue only occurs on linux, the add and show methods will just 
+ * pass through to cardPanel and cardLayout if Base.isLinux() is false.
+ * 
+ * @author George Schneeloch
+ *
+ */
+public class MainWindowCardPanel
+{
+	private final JPanel cardPanel;
+	private final CardLayout cardLayout;
+
+	private final HashMap<String, Component> componentMap;
+
+	public MainWindowCardPanel()
+	{
+		cardLayout = new CardLayout();
+		cardPanel = new JPanel(cardLayout);
+		componentMap = new HashMap<String, Component>();
+	}
+
+	public void add(Component component, String key) {
+		if (Base.isLinux())
+		{
+			componentMap.put(key, component);
+
+			show(key);
+		}
+		else
+		{
+			cardPanel.add(component, key);
+		}
+	}
+
+	/**
+	 * Get the JPanel used by this class. This method should not be used to
+	 * add or remove components, or to show a card; use add() and show() instead
+	 * @return
+	 */
+	public Component getPanel() {
+		return cardPanel;
+	}
+
+	public void show(String key)
+	{
+		if (Base.isLinux())
+		{
+			if (componentMap.containsKey(key))
+			{
+				Component component = componentMap.get(key);
+				// there should only be one widget in cardPanel at any time, 
+				// but just in case, make them all invisible
+				for (Component otherComponent : cardPanel.getComponents())
+				{
+					if (otherComponent.isVisible())
+					{
+						otherComponent.setVisible(false);
+					}
+				}
+				cardPanel.removeAll();
+				cardPanel.add(component, key);
+
+				component.setVisible(true);
+				component.validate();
+			}
+		}
+		else
+		{
+			cardLayout.show(cardPanel, key);
+		}
+	}
+}