When the JViewport scrolls its components, it simply calls setLocation()

which results in the component (and every other component in between that
component and the Sun) becoming invalid. Unfortunately, it isn't kind
enough to also let the RepaintManager know about its jokey business, and
so things simply remain invalid until some other joker comes along and
invalidates everything on God's green earth (like the JTextField). We hack
in a call to revalidate() on our poor unsuspecting scrolled component so
that everything will work properly.


git-svn-id: svn+ssh://src.earth.threerings.net/narya/trunk@1901 542714f4-19e9-0310-aa3c-eee0fc999fb1

src/java/com/threerings/media/SafeScrollPane.java

@@ -1,10 +1,12 @@
 //
-// $Id: SafeScrollPane.java,v 1.4 2002/10/06 20:57:36 mdb Exp $
+// $Id: SafeScrollPane.java,v 1.5 2002/11/05 05:51:18 mdb Exp $
 
 package com.threerings.media;
 
 import java.awt.Component;
+import java.awt.Point;
 
+import javax.swing.JComponent;
 import javax.swing.JScrollPane;
 import javax.swing.JViewport;
 
@@ -24,7 +26,20 @@ public class SafeScrollPane extends JScrollPane
 
     protected JViewport createViewport ()
     {
-        JViewport vp = new JViewport();
+        JViewport vp = new JViewport() {
+            public void setViewPosition (Point p) {
+                super.setViewPosition(p);
+                // simple scroll mode results in setViewPosition causing
+                // our view to become invalid, but nothing ever happens to
+                // queue up a revalidate for said view, so we have to do
+                // it here
+                Component c = getView();
+                if (c instanceof JComponent) {
+                    System.out.println("Revalidating " + c);
+                    ((JComponent)c).revalidate();
+                }
+            }
+        };
         vp.setScrollMode(JViewport.SIMPLE_SCROLL_MODE);
         return vp;
     }