Box alignment and sizing problems

Question

I have a JPanel (using a border layout). Its centre part holds a vertical Box, which itself holds two boxes: The top box holds three labels with centre alignment, and the bottom box holds 5 boxes, each displaying details about a product. All the components in these boxes are left-alignment
The parent JPanel (with the BorderLayout) has its preferred, minimum and maximum sizes specified. Nothihn inside it has sizes specified - in the case of the "product boxes", I do not know exactly how high they will be (it despends on the information they contain). The box that holds the five boxes has a ScrollPane, so that it doesn't really matter how long the content goes.
My problem is that the box holding the five boxes does not adhere to the width limits of the main JPanel. Say the main JPanel is 1000px wide: the
child box's content might stretch for 1500px or 2000px, flowing out of view. Since I have the horizontal scroll bar of the scroll pane set to "As needed", i can scroll across to see the content. But even if I get rid of the scroll pane entirely, the problem still occurs.
The strange thing is I have another JPanel with a very similar structure (Border layout holding box holding 5 boxes), which does not ever seem to exhibit this problem. And also, the problem appears to occur only sometimes.
Anyone seen this before or understand what's going on? I've posted the code. The first block is the constructor for the main JPanel with BorderLayout. The second block is the code for the individual "Product" panels. These are added to the "productListBox" (see below) by a separate SwingWorker thread, after the JPanel has been constructed. The third block is the doInBackground method of that SwingWorker.
Code for JPanel constructor: (Note there is a line commented out. It doesn't seem to matter whether or not this line is in there)
        super(new BorderLayout());
        setPreferredSize(new Dimension(width, height));
        JLabel searchProductLabel = new JLabel("Search a service using the buttons above");
        searchProductLabel.setFont(FontsColors.SUBTITLE_FONT);
        searchProductLabel.setForeground(FontsColors.SUBTITLE_COLOR);
        searchProductLabel.setAlignmentX(CENTER_ALIGNMENT);
        JLabel orLabel = new JLabel("OR");
        orLabel.setFont(FontsColors.TITLE_FONT);
        orLabel.setForeground(FontsColors.TITLE_COLOR);
        orLabel.setAlignmentX(CENTER_ALIGNMENT);
        JLabel instructionsLabel = new JLabel("Search a service on one of these products");
        instructionsLabel.setFont(FontsColors.SUBTITLE_FONT);
        instructionsLabel.setForeground(FontsColors.SUBTITLE_COLOR);
        instructionsLabel.setAlignmentX(CENTER_ALIGNMENT);
        Box instructionsBox = new Box(BoxLayout.Y_AXIS);
        instructionsBox.setAlignmentX(LEFT_ALIGNMENT);
        instructionsBox.add(searchProductLabel);
        instructionsBox.add(Box.createVerticalStrut(PADDING));
        instructionsBox.add(orLabel);
        instructionsBox.add(Box.createVerticalStrut(PADDING));
        instructionsBox.add(instructionsLabel);
        instructionsBox.add(Box.createVerticalStrut(PADDING));
        productsListBox = new Box(BoxLayout.Y_AXIS);
        //productsListBox.setAlignmentX(LEFT_ALIGNMENT);
        Box shoppingBox = new Box(BoxLayout.Y_AXIS);
        shoppingBox.setAlignmentX(LEFT_ALIGNMENT);
        shoppingBox.add(instructionsBox);
        shoppingBox.add(Box.createHorizontalStrut(PADDING));
        shoppingBox.add(productsListBox);
        JScrollPane productsScroll = new JScrollPane(shoppingBox);
        productsScroll.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_NEVER);
        productsScroll.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
        add(productsScroll, BorderLayout.CENTER);Code for product box constructor:
        super(BoxLayout.Y_AXIS);
        Border lineBorder = BorderFactory.createLineBorder(FontsColors.THEME_COLOR);
        Border padding = BorderFactory.createEmptyBorder(BORDER_PADDING, BORDER_PADDING, BORDER_PADDING, BORDER_PADDING);
        setBorder(BorderFactory.createCompoundBorder(lineBorder, padding));
        add(Box.createVerticalStrut(COMPONENT_PADDING));
        String titleBrandString = (data.getBrand() != null) ? (data.getTitle() + " (" + data.getBrand().toUpperCase() + ")") : (data.getTitle());
        Hyperlink titleLink = new Hyperlink(titleBrandString, data.getPageUrl(), FontsColors.TITLE_FONT, FontsColors.TITLE_COLOR);
        titleLink.setAlignmentX(LEFT_ALIGNMENT);
        add(titleLink);
        add(Box.createVerticalStrut(COMPONENT_PADDING));
        JLabel authorLabel = new JLabel(data.getAuthor());
        authorLabel.setFont(FontsColors.SUBTITLE_FONT);
        authorLabel.setForeground(FontsColors.SUBTITLE_COLOR);
        authorLabel.setAlignmentX(LEFT_ALIGNMENT);
        add(authorLabel);
        add(Box.createVerticalStrut(COMPONENT_PADDING));
        JTextArea descriptionArea = new JTextArea(data.getDescription());
        descriptionArea.setEditable(false);
        descriptionArea.setLineWrap(true);
        descriptionArea.setWrapStyleWord(true);
        descriptionArea.setAlignmentX(LEFT_ALIGNMENT);
        add(descriptionArea);
        add(Box.createVerticalStrut(COMPONENT_PADDING));
        if(data.getPrice() != null)
            String priceConditionString = data.getPrice();
            JLabel priceConditionLabel = new JLabel(priceConditionString);
            priceConditionLabel.setFont(FontsColors.EMPHASIS_FONT);
            priceConditionLabel.setForeground(FontsColors.EMPHASIS_COLOR);
            add(priceConditionLabel);
        add(Box.createVerticalStrut(COMPONENT_PADDING));
        ServiceButtonPanel serviceButtonPanel = new ServiceButtonPanel();
        serviceButtonPanel.addServiceButtonActions(new SetProductSearchStringActionListener());
        serviceButtonPanel.setAlignmentX(LEFT_ALIGNMENT);
        add(serviceButtonPanel);
        add(Box.createVerticalStrut(COMPONENT_PADDING));
        searchString = data.getTitle();Code for SwingWorker that adds the product boxes:
        protected Void doInBackground() throws Exception
            for(int index = 0; index < products.size(); index++)
                ProductInfoPanel panel = new ProductInfoPanel(products.get(index));
                Border padding = BorderFactory.createEmptyBorder(PADDING, PADDING, PADDING, PADDING);
                panel.setBorder(BorderFactory.createCompoundBorder(padding, panel.getBorder()));
                productsListBox.add(panel);
            validate();
            return null;
        }Edited by: 803559 on 13-May-2011 00:06

Answer 1

jduprez
You have solved the problem inadvertently
No. Twice no.
1) You have solved the problem. Not me. I just gave a push in the (apparently) right direction. You deserve more credits.
2) Take my word for it, this was anything but inadvertently . Indeed it's a well-known trait of the SSCCE "methodology", that the developer often discovers the origin of the problem, and hopefully finds the solution as well.
- If you demonstrate the problem in shorter code, means there are less suspects to investigate.
- If you don't, then you start adding things to look more than the real program, one thing at a time, until you find one thing that introduces the problem.
I'm not promoting SSCCE to prevent or refrain people from posting questions in the forum. I'm a addict of this forum, and I'm the first one frustrated when there are no questions here.
It's just that using SSCCE often eliminates trivial problem before they have to be worded here, and leaves mostly interesting problems to investigate. And for those, having a complete runnable example is easier to copy/paste in an IDE to try out and play with.
I made up an SSCCE as you said. Because I did not want to have to bother with accessing Google Shopping (which is where the program gets the product information) i made a bunch of fake productions, all called "Xbox 360". Everything was fine.Excellent (and straight to the point of the methodology).
You then witnessed that the problem was not where you thought it were initially (I'm stretching your words a bit for the purpose of the demonstration, but it required a combination of code and certain data to exhibit the problem).
It turned out that it was the Title JLabel of the individual product information panels that was causing it to stretch beyond its bounds. I didn't pick up on it, because the problem arose even if the JLabel text didn't take up the entire width of the panel - once it got about 2/3 of the way across, the width would increase.I'm surprised again. Don't you have another widget on the same "line", in addition to the label?
But I trust your findings (without an SSCCE I can't commit myself :o)
I'll try switching to a multiline text holder so that the text can wrap around.Yes, that sounds sensible for such a thing as "product information".
Thank you, jduprez. I'll remember to post a SSCCE next time I have an issue.Great. I'm glad you solved your problem, and I'm glad I haven't deterred you from posting at all! :o)
Darryl: thank you for clearning that up. I've been confused as to which one to use.Yes.
I will post something one of these days to have that cleared up (the tutorial recommends to brutally call revalidate()repaint()+ , but I think that's exagerated: http://download.oracle.com/javase/tutorial/uiswing/layout/howLayoutWorks.html, http://download.oracle.com/javase/tutorial/uiswing/layout/problems.html)
Edited by: jduprez on May 13, 2011 1:50 PM