ui/src/main/java/ucar/nc2/ui/widget/ImprovedFileChooser.java
@Override public int showDialog(Component parent, String approveButtonText) throws HeadlessException {
        int returnValue = super.showDialog(parent, approveButtonText);
        this.dialog = null;  // dialog was disposed in super-method. Null out so we don't try to use it.
        return returnValue;
    }
@Override public int showDialog(Component parent, String approveButtonText) throws HeadlessException {
        int returnValue = super.showDialog(parent, approveButtonText);
        this.dialog = null;  // dialog was disposed in super-method. Null out so we don't try to use it.
        return returnValue;
    }
///////////////////////////////////////////////// JFileChooser ///////////////////////////////////////////////////