The ChartPanel class overrides paintComponent(Graphics) and casts the
incoming Graphics object the Graphics2D subclass - this is very common
in Swing apps as a way to gain access to Java2D features for drawing on
Swing components. I'm almost certain that the Graphics object is
guaranteed to be a Graphics2D instance, and the original method
signature is maintained for backwards compatibility only, although this
isn't mentioned in the API specification. The only reference I've been
able to find is this one in the Java tutorial:
http://java.sun.com/docs/books/tutorial/uiswing/14painting/practice.html
I think many applications are going to fail on our implementation until
we get good Graphics2D support into our JComponent (many custom look and
feel implementations rely on it, for starters).
Regards,
Dave
Audrius Meskauskas wrote:
This is because jMemorize overrides the JTable.columnMarginChanged
that is fired from the JTable constructor, when the user - derived
class is not yet initialised. This can be easily fixed by initialising
the table column model befor the table listeners are installed on it,
I have comitted such patch. Unfortunately, this brings us to the
second exception, related to the JFreeChart:
java.lang.ClassCastException: gnu/java/awt/peer/gtk/GdkGraphics
at org.jfree.chart.ChartPanel.paintComponent (ChartPanel.java:905)
at javax.swing.JComponent.paint (JComponent.java:1583)
at javax.swing.JComponent.paintChildren (JComponent.java:1700)
at javax.swing.JComponent.paint (JComponent.java:1585)
at javax.swing.JComponent.paintChildren (JComponent.java:1700)
at javax.swing.JSplitPane.paintChildren (JSplitPane.java:538)
at javax.swing.JComponent.paint (JComponent.java:1585)
at javax.swing.JComponent.paintChildren (JComponent.java:1700)
at javax.swing.JComponent.paint (JComponent.java:1585)
at javax.swing.JComponent.paintChildren (JComponent.java:1700)
at javax.swing.JSplitPane.paintChildren (JSplitPane.java:538)
at javax.swing.JComponent.paint (JComponent.java:1585)
at javax.swing.JComponent.paintChildren (JComponent.java:1700)
at javax.swing.JComponent.paint (JComponent.java:1585)
at javax.swing.JComponent.paintChildren (JComponent.java:1700)
at javax.swing.JComponent.paint (JComponent.java:1585)
at javax.swing.JLayeredPane.paint (JLayeredPane.java:647)
at javax.swing.JComponent.paintChildren (JComponent.java:1700)
Probably our JFreeChart experts could look at this.
Regards
Audrius.
Robert Schuster wrote:
Hi,
I added jMemorize[0] to the list of Free Swing apps. I just stumbled
over the
app and tried to run it but it fails with a NPE:
java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invokeNative (Native Method)
at java.lang.reflect.Method.invoke (Method.java:355)
at jamvm.java.lang.JarLauncher.main (JarLauncher.java:50)
Caused by: java.lang.NullPointerException
at jmemorize.gui.swing.CardTable.columnMarginChanged (Unknown Source)
at javax.swing.table.DefaultTableColumnModel.fireColumnMarginChanged
(DefaultTableColumnModel.java:493)
at javax.swing.table.DefaultTableColumnModel.setColumnMargin
(DefaultTableColumnModel.java:171)
at javax.swing.JTable.setIntercellSpacing (JTable.java:2950)
at javax.swing.JTable.initializeLocalVars (JTable.java:1720)
at javax.swing.JTable.<init> (JTable.java:1664)
at javax.swing.JTable.<init> (JTable.java:1582)
at jmemorize.gui.swing.CardTable.<init> (Unknown Source)
at jmemorize.gui.swing.FindFrame.<init> (Unknown Source)
at jmemorize.gui.swing.MainFrame.<init> (Unknown Source)
at jmemorize.core.Main.run (Unknown Source)
at jmemorize.core.Main.main (Unknown Source)
at java.lang.reflect.Method.invokeNative (Native Method)
...2 more
Since there are some Swing hackers who frequently work on JTable this
might be a
low hanging fruit for them.
cya
Robert
[0] - http://riad.de/jmemorize
