NullPointerException: Cannot read field "width" because "this.componentInnards" is null

Created by: benfry

Seen in 4.0, but not clear if this is downstream problems caused by https://github.com/processing/processing4/issues/530 or if it's an error triggered by changing between themes.

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException: Cannot read field "width" because "this.componentInnards" is null
at java.desktop/javax.swing.plaf.basic.BasicProgressBarUI.updateSizes(BasicProgressBarUI.java:542)
at java.desktop/javax.swing.plaf.basic.BasicProgressBarUI.getBox(BasicProgressBarUI.java:499)
at java.desktop/javax.swing.plaf.basic.BasicProgressBarUI.paintIndeterminate(BasicProgressBarUI.java:656)
at java.desktop/javax.swing.plaf.basic.BasicProgressBarUI.paint(BasicProgressBarUI.java:464)
at java.desktop/javax.swing.plaf.ComponentUI.update(ComponentUI.java:161)
at java.desktop/javax.swing.JComponent.paintComponent(JComponent.java:842)
at java.desktop/javax.swing.JComponent.paint(JComponent.java:1119)
at java.desktop/javax.swing.JComponent.paintToOffscreen(JComponent.java:5311)
at java.desktop/javax.swing.RepaintManager$PaintManager.paintDoubleBufferedImpl(RepaintManager.java:1657)
at java.desktop/javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1632)
at java.desktop/javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1570)
at java.desktop/javax.swing.RepaintManager.paint(RepaintManager.java:1337)
at java.desktop/javax.swing.JComponent._paintImmediately(JComponent.java:5259)
at java.desktop/javax.swing.JComponent.paintImmediately(JComponent.java:5069)
at java.desktop/javax.swing.RepaintManager$4.run(RepaintManager.java:879)
at java.desktop/javax.swing.RepaintManager$4.run(RepaintManager.java:862)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.desktop/javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:862)
at java.desktop/javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:835)
at java.desktop/javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:784)
at java.desktop/javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1898)
at java.desktop/java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:318)
at java.desktop/java.awt.EventQueue.dispatchEventImpl(EventQueue.java:771)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:722)
at java.desktop/java.awt.EventQueue$4.run(EventQueue.java:716)
at java.base/java.security.AccessController.doPrivileged(AccessController.java:399)
at java.base/java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.desktop/java.awt.EventQueue.dispatchEvent(EventQueue.java:741)
at java.desktop/java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:203)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:124)
at java.desktop/java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:113)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:109)
at java.desktop/java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.desktop/java.awt.EventDispatchThread.run(EventDispatchThread.java:90)

Beginne damit, den Fehler in Processing 4 beim Wechseln von Themes zu reproduzieren, und verfolge dann den Pfad zum Zeichnen der Fortschrittsleiste, der im Stacktrace von BasicProgressBarUI angezeigt wird. Vergleiche das Verhalten mit dem möglichen nachgelagerten Problem in processing4#530; abgeschlossen ist die Aufgabe, wenn Theme-Wechsel diese NullPointerException nicht mehr erzeugen.