JAL-1497 check to see if tree structure is ready for display, and show a 'tree loadin...

diff --git a/src/jalview/gui/TreeCanvas.java b/src/jalview/gui/TreeCanvas.java
index 9e2e582..97cca4b 100755 (executable)
--- a/src/jalview/gui/TreeCanvas.java
+++ b/src/jalview/gui/TreeCanvas.java
@@ -667,9 +667,12 @@ public class TreeCanvas extends JPanel implements MouseListener, Runnable,
             RenderingHints.VALUE_ANTIALIAS_ON);
     g2.setColor(Color.white);
     g2.fillRect(0, 0, width, height);
-
     g2.setFont(font);
 
+    if (longestName==null || tree ==null)
+    {
+      g2.drawString("Calculating tree.",20,20);
+    }
     offy = font.getSize() + 10;
 
     fm = g2.getFontMetrics(font);