Crash in combobox with custom renderer after switching to FlatLaf

[kirill-grouchnikov]

public class Test {
    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(new NimbusLookAndFeel());
                } catch (Throwable t) {
                    t.printStackTrace(System.err);
                }

                JComboBox comboColors = new JComboBox<>(new Color[] {new Color(255, 128, 128),
                        new Color(128, 255, 128), new Color(128, 128, 255), new Color(255, 255, 128),
                        new Color(255, 128, 255), new Color(128, 255, 255)});

                comboColors.setRenderer(new DefaultListCellRenderer() {
                    @Override
                    public Component getListCellRendererComponent(JList list,
                            Object value, int index, boolean isSelected,
                            boolean cellHasFocus) {
                        Color color = (Color) value;
                        Component result = super.getListCellRendererComponent(list,
                                color.getRed() + ":" + color.getGreen() + ":" + color.getBlue(),
                                index, isSelected, cellHasFocus);
                            result.setBackground(color);
                        return result;
                    }
                });

                JButton toFlat = new JButton("Set FlatDark!");
                toFlat.addActionListener(new ActionListener() {
                    @Override
                    public void actionPerformed(ActionEvent e) {
                        SwingUtilities.invokeLater(new Runnable() {
                            @Override
                            public void run() {
                                try {
                                    UIManager.setLookAndFeel("com.formdev.flatlaf.FlatDarkLaf");
                                    for (Window w : Window.getWindows()) {
                                        SwingUtilities.updateComponentTreeUI(w);
                                    }
                                } catch (Throwable t) {
                                    t.printStackTrace(System.err);
                                }
                            }
                        });
                    }
                });

                JFrame frame = new JFrame("Combo test");
                frame.setLayout(new BorderLayout());
                frame.add(comboColors, BorderLayout.NORTH);
                frame.add(toFlat, BorderLayout.SOUTH);
                frame.setSize(400, 400);
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }
}

Click the "Set FlatDark!" button and then click the combo at the top. Result:

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
	at java.desktop/javax.swing.plaf.basic.BasicComboPopup.getPopupHeightForRowCount(BasicComboPopup.java:1283)
	at java.desktop/javax.swing.plaf.basic.BasicComboPopup.getPopupLocation(BasicComboPopup.java:1369)
	at java.desktop/javax.swing.plaf.basic.BasicComboPopup.show(BasicComboPopup.java:234)
	at java.desktop/javax.swing.plaf.basic.BasicComboPopup.togglePopup(BasicComboPopup.java:1218)
	at java.desktop/javax.swing.plaf.basic.BasicComboPopup$Handler.mousePressed(BasicComboPopup.java:897)
	at java.desktop/java.awt.AWTEventMulticaster.mousePressed(AWTEventMulticaster.java:287)
	at java.desktop/java.awt.Component.processMouseEvent(Component.java:6633)

This is on 0.14

[JFormDesigner]

many thanks, fixed in 0.15